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package java.util;

import java.lang.reflect.Array;
import java.util.concurrent.ForkJoinPool;
import java.util.function.BinaryOperator;
import java.util.function.Consumer;
import java.util.function.DoubleBinaryOperator;
import java.util.function.IntBinaryOperator;
import java.util.function.IntFunction;
import java.util.function.IntToDoubleFunction;
import java.util.function.IntToLongFunction;
import java.util.function.IntUnaryOperator;
import java.util.function.LongBinaryOperator;
import java.util.function.UnaryOperator;
import java.util.stream.DoubleStream;
import java.util.stream.IntStream;
import java.util.stream.LongStream;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;

This class contains various methods for manipulating arrays (such as sorting and searching). This class also contains a static factory that allows arrays to be viewed as lists.

The methods in this class all throw a NullPointerException, if the specified array reference is null, except where noted.

The documentation for the methods contained in this class includes briefs description of the implementations. Such descriptions should be regarded as implementation notes, rather than parts of the specification. Implementors should feel free to substitute other algorithms, so long as the specification itself is adhered to. (For example, the algorithm used by sort(Object[]) does not have to be a MergeSort, but it does have to be stable.)

This class is a member of the Java Collections Framework.

Author:Josh Bloch, Neal Gafter, John Rose
Since: 1.2
/** * This class contains various methods for manipulating arrays (such as * sorting and searching). This class also contains a static factory * that allows arrays to be viewed as lists. * * <p>The methods in this class all throw a {@code NullPointerException}, * if the specified array reference is null, except where noted. * * <p>The documentation for the methods contained in this class includes * briefs description of the <i>implementations</i>. Such descriptions should * be regarded as <i>implementation notes</i>, rather than parts of the * <i>specification</i>. Implementors should feel free to substitute other * algorithms, so long as the specification itself is adhered to. (For * example, the algorithm used by {@code sort(Object[])} does not have to be * a MergeSort, but it does have to be <i>stable</i>.) * * <p>This class is a member of the * <a href="{@docRoot}/../technotes/guides/collections/index.html"> * Java Collections Framework</a>. * * @author Josh Bloch * @author Neal Gafter * @author John Rose * @since 1.2 */
public class Arrays {
The minimum array length below which a parallel sorting algorithm will not further partition the sorting task. Using smaller sizes typically results in memory contention across tasks that makes parallel speedups unlikely.
/** * The minimum array length below which a parallel sorting * algorithm will not further partition the sorting task. Using * smaller sizes typically results in memory contention across * tasks that makes parallel speedups unlikely. */
private static final int MIN_ARRAY_SORT_GRAN = 1 << 13; // Suppresses default constructor, ensuring non-instantiability. private Arrays() {}
A comparator that implements the natural ordering of a group of mutually comparable elements. May be used when a supplied comparator is null. To simplify code-sharing within underlying implementations, the compare method only declares type Object for its second argument. Arrays class implementor's note: It is an empirical matter whether ComparableTimSort offers any performance benefit over TimSort used with this comparator. If not, you are better off deleting or bypassing ComparableTimSort. There is currently no empirical case for separating them for parallel sorting, so all public Object parallelSort methods use the same comparator based implementation.
/** * A comparator that implements the natural ordering of a group of * mutually comparable elements. May be used when a supplied * comparator is null. To simplify code-sharing within underlying * implementations, the compare method only declares type Object * for its second argument. * * Arrays class implementor's note: It is an empirical matter * whether ComparableTimSort offers any performance benefit over * TimSort used with this comparator. If not, you are better off * deleting or bypassing ComparableTimSort. There is currently no * empirical case for separating them for parallel sorting, so all * public Object parallelSort methods use the same comparator * based implementation. */
static final class NaturalOrder implements Comparator<Object> { @SuppressWarnings("unchecked") public int compare(Object first, Object second) { return ((Comparable<Object>)first).compareTo(second); } static final NaturalOrder INSTANCE = new NaturalOrder(); }
Checks that fromIndex and toIndex are in the range and throws an exception if they aren't.
/** * Checks that {@code fromIndex} and {@code toIndex} are in * the range and throws an exception if they aren't. */
private static void rangeCheck(int arrayLength, int fromIndex, int toIndex) { if (fromIndex > toIndex) { throw new IllegalArgumentException( "fromIndex(" + fromIndex + ") > toIndex(" + toIndex + ")"); } if (fromIndex < 0) { throw new ArrayIndexOutOfBoundsException(fromIndex); } if (toIndex > arrayLength) { throw new ArrayIndexOutOfBoundsException(toIndex); } } /* * Sorting methods. Note that all public "sort" methods take the * same form: Performing argument checks if necessary, and then * expanding arguments into those required for the internal * implementation methods residing in other package-private * classes (except for legacyMergeSort, included in this class). */
Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
/** * Sorts the specified array into ascending numerical order. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted */
public static void sort(int[] a) { DualPivotQuicksort.sort(a, 0, a.length - 1, null, 0, 0); }
Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
/** * Sorts the specified range of the array into ascending order. The range * to be sorted extends from the index {@code fromIndex}, inclusive, to * the index {@code toIndex}, exclusive. If {@code fromIndex == toIndex}, * the range to be sorted is empty. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} */
public static void sort(int[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); }
Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
/** * Sorts the specified array into ascending numerical order. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted */
public static void sort(long[] a) { DualPivotQuicksort.sort(a, 0, a.length - 1, null, 0, 0); }
Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
/** * Sorts the specified range of the array into ascending order. The range * to be sorted extends from the index {@code fromIndex}, inclusive, to * the index {@code toIndex}, exclusive. If {@code fromIndex == toIndex}, * the range to be sorted is empty. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} */
public static void sort(long[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); }
Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
/** * Sorts the specified array into ascending numerical order. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted */
public static void sort(short[] a) { DualPivotQuicksort.sort(a, 0, a.length - 1, null, 0, 0); }
Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
/** * Sorts the specified range of the array into ascending order. The range * to be sorted extends from the index {@code fromIndex}, inclusive, to * the index {@code toIndex}, exclusive. If {@code fromIndex == toIndex}, * the range to be sorted is empty. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} */
public static void sort(short[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); }
Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
/** * Sorts the specified array into ascending numerical order. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted */
public static void sort(char[] a) { DualPivotQuicksort.sort(a, 0, a.length - 1, null, 0, 0); }
Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
/** * Sorts the specified range of the array into ascending order. The range * to be sorted extends from the index {@code fromIndex}, inclusive, to * the index {@code toIndex}, exclusive. If {@code fromIndex == toIndex}, * the range to be sorted is empty. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} */
public static void sort(char[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); }
Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
/** * Sorts the specified array into ascending numerical order. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted */
public static void sort(byte[] a) { DualPivotQuicksort.sort(a, 0, a.length - 1); }
Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
/** * Sorts the specified range of the array into ascending order. The range * to be sorted extends from the index {@code fromIndex}, inclusive, to * the index {@code toIndex}, exclusive. If {@code fromIndex == toIndex}, * the range to be sorted is empty. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} */
public static void sort(byte[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); DualPivotQuicksort.sort(a, fromIndex, toIndex - 1); }
Sorts the specified array into ascending numerical order.

The < relation does not provide a total order on all float values: -0.0f == 0.0f is true and a Float.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Float.compareTo: -0.0f is treated as less than value 0.0f and Float.NaN is considered greater than any other value and all Float.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
/** * Sorts the specified array into ascending numerical order. * * <p>The {@code <} relation does not provide a total order on all float * values: {@code -0.0f == 0.0f} is {@code true} and a {@code Float.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Float#compareTo}: {@code -0.0f} is treated as less than value * {@code 0.0f} and {@code Float.NaN} is considered greater than any * other value and all {@code Float.NaN} values are considered equal. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted */
public static void sort(float[] a) { DualPivotQuicksort.sort(a, 0, a.length - 1, null, 0, 0); }
Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

The < relation does not provide a total order on all float values: -0.0f == 0.0f is true and a Float.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Float.compareTo: -0.0f is treated as less than value 0.0f and Float.NaN is considered greater than any other value and all Float.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
/** * Sorts the specified range of the array into ascending order. The range * to be sorted extends from the index {@code fromIndex}, inclusive, to * the index {@code toIndex}, exclusive. If {@code fromIndex == toIndex}, * the range to be sorted is empty. * * <p>The {@code <} relation does not provide a total order on all float * values: {@code -0.0f == 0.0f} is {@code true} and a {@code Float.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Float#compareTo}: {@code -0.0f} is treated as less than value * {@code 0.0f} and {@code Float.NaN} is considered greater than any * other value and all {@code Float.NaN} values are considered equal. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} */
public static void sort(float[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); }
Sorts the specified array into ascending numerical order.

The < relation does not provide a total order on all double values: -0.0d == 0.0d is true and a Double.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Double.compareTo: -0.0d is treated as less than value 0.0d and Double.NaN is considered greater than any other value and all Double.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
/** * Sorts the specified array into ascending numerical order. * * <p>The {@code <} relation does not provide a total order on all double * values: {@code -0.0d == 0.0d} is {@code true} and a {@code Double.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Double#compareTo}: {@code -0.0d} is treated as less than value * {@code 0.0d} and {@code Double.NaN} is considered greater than any * other value and all {@code Double.NaN} values are considered equal. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted */
public static void sort(double[] a) { DualPivotQuicksort.sort(a, 0, a.length - 1, null, 0, 0); }
Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

The < relation does not provide a total order on all double values: -0.0d == 0.0d is true and a Double.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Double.compareTo: -0.0d is treated as less than value 0.0d and Double.NaN is considered greater than any other value and all Double.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
/** * Sorts the specified range of the array into ascending order. The range * to be sorted extends from the index {@code fromIndex}, inclusive, to * the index {@code toIndex}, exclusive. If {@code fromIndex == toIndex}, * the range to be sorted is empty. * * <p>The {@code <} relation does not provide a total order on all double * values: {@code -0.0d == 0.0d} is {@code true} and a {@code Double.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Double#compareTo}: {@code -0.0d} is treated as less than value * {@code 0.0d} and {@code Double.NaN} is considered greater than any * other value and all {@code Double.NaN} values are considered equal. * * <p>Implementation note: The sorting algorithm is a Dual-Pivot Quicksort * by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm * offers O(n log(n)) performance on many data sets that cause other * quicksorts to degrade to quadratic performance, and is typically * faster than traditional (one-pivot) Quicksort implementations. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} */
public static void sort(double[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); }
Sorts the specified array into ascending numerical order.
Params:
  • a – the array to be sorted
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array into ascending numerical order. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(byte[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(byte[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param a the array to be sorted * * @since 1.8 */
public static void parallelSort(byte[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, 0, n - 1); else new ArraysParallelSortHelpers.FJByte.Sorter (null, a, new byte[n], 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified range of the array into ascending numerical order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.
Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the array into ascending numerical order. * The range to be sorted extends from the index {@code fromIndex}, * inclusive, to the index {@code toIndex}, exclusive. If * {@code fromIndex == toIndex}, the range to be sorted is empty. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(byte[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(byte[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} * * @since 1.8 */
public static void parallelSort(byte[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, fromIndex, toIndex - 1); else new ArraysParallelSortHelpers.FJByte.Sorter (null, a, new byte[n], fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified array into ascending numerical order.
Params:
  • a – the array to be sorted
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array into ascending numerical order. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(char[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(char[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param a the array to be sorted * * @since 1.8 */
public static void parallelSort(char[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, 0, n - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJChar.Sorter (null, a, new char[n], 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified range of the array into ascending numerical order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.
Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the array into ascending numerical order. * The range to be sorted extends from the index {@code fromIndex}, * inclusive, to the index {@code toIndex}, exclusive. If * {@code fromIndex == toIndex}, the range to be sorted is empty. * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(char[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(char[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} * * @since 1.8 */
public static void parallelSort(char[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJChar.Sorter (null, a, new char[n], fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified array into ascending numerical order.
Params:
  • a – the array to be sorted
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array into ascending numerical order. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(short[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(short[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param a the array to be sorted * * @since 1.8 */
public static void parallelSort(short[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, 0, n - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJShort.Sorter (null, a, new short[n], 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified range of the array into ascending numerical order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.
Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the array into ascending numerical order. * The range to be sorted extends from the index {@code fromIndex}, * inclusive, to the index {@code toIndex}, exclusive. If * {@code fromIndex == toIndex}, the range to be sorted is empty. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(short[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(short[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} * * @since 1.8 */
public static void parallelSort(short[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJShort.Sorter (null, a, new short[n], fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified array into ascending numerical order.
Params:
  • a – the array to be sorted
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array into ascending numerical order. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(int[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(int[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param a the array to be sorted * * @since 1.8 */
public static void parallelSort(int[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, 0, n - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJInt.Sorter (null, a, new int[n], 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified range of the array into ascending numerical order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.
Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the array into ascending numerical order. * The range to be sorted extends from the index {@code fromIndex}, * inclusive, to the index {@code toIndex}, exclusive. If * {@code fromIndex == toIndex}, the range to be sorted is empty. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(int[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(int[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} * * @since 1.8 */
public static void parallelSort(int[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJInt.Sorter (null, a, new int[n], fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified array into ascending numerical order.
Params:
  • a – the array to be sorted
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array into ascending numerical order. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(long[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(long[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param a the array to be sorted * * @since 1.8 */
public static void parallelSort(long[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, 0, n - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJLong.Sorter (null, a, new long[n], 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified range of the array into ascending numerical order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.
Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the array into ascending numerical order. * The range to be sorted extends from the index {@code fromIndex}, * inclusive, to the index {@code toIndex}, exclusive. If * {@code fromIndex == toIndex}, the range to be sorted is empty. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(long[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(long[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} * * @since 1.8 */
public static void parallelSort(long[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJLong.Sorter (null, a, new long[n], fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified array into ascending numerical order.

The < relation does not provide a total order on all float values: -0.0f == 0.0f is true and a Float.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Float.compareTo: -0.0f is treated as less than value 0.0f and Float.NaN is considered greater than any other value and all Float.NaN values are considered equal.

Params:
  • a – the array to be sorted
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array into ascending numerical order. * * <p>The {@code <} relation does not provide a total order on all float * values: {@code -0.0f == 0.0f} is {@code true} and a {@code Float.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Float#compareTo}: {@code -0.0f} is treated as less than value * {@code 0.0f} and {@code Float.NaN} is considered greater than any * other value and all {@code Float.NaN} values are considered equal. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(float[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(float[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param a the array to be sorted * * @since 1.8 */
public static void parallelSort(float[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, 0, n - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJFloat.Sorter (null, a, new float[n], 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified range of the array into ascending numerical order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

The < relation does not provide a total order on all float values: -0.0f == 0.0f is true and a Float.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Float.compareTo: -0.0f is treated as less than value 0.0f and Float.NaN is considered greater than any other value and all Float.NaN values are considered equal.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the array into ascending numerical order. * The range to be sorted extends from the index {@code fromIndex}, * inclusive, to the index {@code toIndex}, exclusive. If * {@code fromIndex == toIndex}, the range to be sorted is empty. * * <p>The {@code <} relation does not provide a total order on all float * values: {@code -0.0f == 0.0f} is {@code true} and a {@code Float.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Float#compareTo}: {@code -0.0f} is treated as less than value * {@code 0.0f} and {@code Float.NaN} is considered greater than any * other value and all {@code Float.NaN} values are considered equal. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(float[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(float[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} * * @since 1.8 */
public static void parallelSort(float[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJFloat.Sorter (null, a, new float[n], fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified array into ascending numerical order.

The < relation does not provide a total order on all double values: -0.0d == 0.0d is true and a Double.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Double.compareTo: -0.0d is treated as less than value 0.0d and Double.NaN is considered greater than any other value and all Double.NaN values are considered equal.

Params:
  • a – the array to be sorted
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array into ascending numerical order. * * <p>The {@code <} relation does not provide a total order on all double * values: {@code -0.0d == 0.0d} is {@code true} and a {@code Double.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Double#compareTo}: {@code -0.0d} is treated as less than value * {@code 0.0d} and {@code Double.NaN} is considered greater than any * other value and all {@code Double.NaN} values are considered equal. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(double[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(double[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param a the array to be sorted * * @since 1.8 */
public static void parallelSort(double[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, 0, n - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJDouble.Sorter (null, a, new double[n], 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified range of the array into ascending numerical order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

The < relation does not provide a total order on all double values: -0.0d == 0.0d is true and a Double.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Double.compareTo: -0.0d is treated as less than value 0.0d and Double.NaN is considered greater than any other value and all Double.NaN values are considered equal.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element, inclusive, to be sorted
  • toIndex – the index of the last element, exclusive, to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the array into ascending numerical order. * The range to be sorted extends from the index {@code fromIndex}, * inclusive, to the index {@code toIndex}, exclusive. If * {@code fromIndex == toIndex}, the range to be sorted is empty. * * <p>The {@code <} relation does not provide a total order on all double * values: {@code -0.0d == 0.0d} is {@code true} and a {@code Double.NaN} * value compares neither less than, greater than, nor equal to any value, * even itself. This method uses the total order imposed by the method * {@link Double#compareTo}: {@code -0.0d} is treated as less than value * {@code 0.0d} and {@code Double.NaN} is considered greater than any * other value and all {@code Double.NaN} values are considered equal. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(double[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(double[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param a the array to be sorted * @param fromIndex the index of the first element, inclusive, to be sorted * @param toIndex the index of the last element, exclusive, to be sorted * * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > a.length} * * @since 1.8 */
public static void parallelSort(double[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) DualPivotQuicksort.sort(a, fromIndex, toIndex - 1, null, 0, 0); else new ArraysParallelSortHelpers.FJDouble.Sorter (null, a, new double[n], fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g).invoke(); }
Sorts the specified array of objects into ascending order, according to the natural ordering of its elements. All elements in the array must implement the Comparable interface. Furthermore, all elements in the array must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Params:
  • a – the array to be sorted
Type parameters:
  • <T> – the class of the objects to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array of objects into ascending order, according * to the {@linkplain Comparable natural ordering} of its elements. * All elements in the array must implement the {@link Comparable} * interface. Furthermore, all elements in the array must be * <i>mutually comparable</i> (that is, {@code e1.compareTo(e2)} must * not throw a {@code ClassCastException} for any elements {@code e1} * and {@code e2} in the array). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(Object[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(Object[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param <T> the class of the objects to be sorted * @param a the array to be sorted * * @throws ClassCastException if the array contains elements that are not * <i>mutually comparable</i> (for example, strings and integers) * @throws IllegalArgumentException (optional) if the natural * ordering of the array elements is found to violate the * {@link Comparable} contract * * @since 1.8 */
@SuppressWarnings("unchecked") public static <T extends Comparable<? super T>> void parallelSort(T[] a) { int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) TimSort.sort(a, 0, n, NaturalOrder.INSTANCE, null, 0, 0); else new ArraysParallelSortHelpers.FJObject.Sorter<T> (null, a, (T[])Array.newInstance(a.getClass().getComponentType(), n), 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g, NaturalOrder.INSTANCE).invoke(); }
Sorts the specified range of the specified array of objects into ascending order, according to the natural ordering of its elements. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.) All elements in this range must implement the Comparable interface. Furthermore, all elements in this range must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element (inclusive) to be sorted
  • toIndex – the index of the last element (exclusive) to be sorted
Type parameters:
  • <T> – the class of the objects to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the specified array of objects into * ascending order, according to the * {@linkplain Comparable natural ordering} of its * elements. The range to be sorted extends from index * {@code fromIndex}, inclusive, to index {@code toIndex}, exclusive. * (If {@code fromIndex==toIndex}, the range to be sorted is empty.) All * elements in this range must implement the {@link Comparable} * interface. Furthermore, all elements in this range must be <i>mutually * comparable</i> (that is, {@code e1.compareTo(e2)} must not throw a * {@code ClassCastException} for any elements {@code e1} and * {@code e2} in the array). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(Object[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(Object[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param <T> the class of the objects to be sorted * @param a the array to be sorted * @param fromIndex the index of the first element (inclusive) to be * sorted * @param toIndex the index of the last element (exclusive) to be sorted * @throws IllegalArgumentException if {@code fromIndex > toIndex} or * (optional) if the natural ordering of the array elements is * found to violate the {@link Comparable} contract * @throws ArrayIndexOutOfBoundsException if {@code fromIndex < 0} or * {@code toIndex > a.length} * @throws ClassCastException if the array contains elements that are * not <i>mutually comparable</i> (for example, strings and * integers). * * @since 1.8 */
@SuppressWarnings("unchecked") public static <T extends Comparable<? super T>> void parallelSort(T[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) TimSort.sort(a, fromIndex, toIndex, NaturalOrder.INSTANCE, null, 0, 0); else new ArraysParallelSortHelpers.FJObject.Sorter<T> (null, a, (T[])Array.newInstance(a.getClass().getComponentType(), n), fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g, NaturalOrder.INSTANCE).invoke(); }
Sorts the specified array of objects according to the order induced by the specified comparator. All elements in the array must be mutually comparable by the specified comparator (that is, c.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Params:
  • a – the array to be sorted
  • cmp – the comparator to determine the order of the array. A null value indicates that the elements' natural ordering should be used.
Type parameters:
  • <T> – the class of the objects to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified array of objects according to the order induced by * the specified comparator. All elements in the array must be * <i>mutually comparable</i> by the specified comparator (that is, * {@code c.compare(e1, e2)} must not throw a {@code ClassCastException} * for any elements {@code e1} and {@code e2} in the array). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(Object[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(Object[]) Arrays.sort} method. The algorithm requires a * working space no greater than the size of the original array. The * {@link ForkJoinPool#commonPool() ForkJoin common pool} is used to * execute any parallel tasks. * * @param <T> the class of the objects to be sorted * @param a the array to be sorted * @param cmp the comparator to determine the order of the array. A * {@code null} value indicates that the elements' * {@linkplain Comparable natural ordering} should be used. * @throws ClassCastException if the array contains elements that are * not <i>mutually comparable</i> using the specified comparator * @throws IllegalArgumentException (optional) if the comparator is * found to violate the {@link java.util.Comparator} contract * * @since 1.8 */
@SuppressWarnings("unchecked") public static <T> void parallelSort(T[] a, Comparator<? super T> cmp) { if (cmp == null) cmp = NaturalOrder.INSTANCE; int n = a.length, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) TimSort.sort(a, 0, n, cmp, null, 0, 0); else new ArraysParallelSortHelpers.FJObject.Sorter<T> (null, a, (T[])Array.newInstance(a.getClass().getComponentType(), n), 0, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g, cmp).invoke(); }
Sorts the specified range of the specified array of objects according to the order induced by the specified comparator. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.) All elements in the range must be mutually comparable by the specified comparator (that is, c.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the range).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element (inclusive) to be sorted
  • toIndex – the index of the last element (exclusive) to be sorted
  • cmp – the comparator to determine the order of the array. A null value indicates that the elements' natural ordering should be used.
Type parameters:
  • <T> – the class of the objects to be sorted
Throws:
Implementation Note:The sorting algorithm is a parallel sort-merge that breaks the array into sub-arrays that are themselves sorted and then merged. When the sub-array length reaches a minimum granularity, the sub-array is sorted using the appropriate Arrays.sort method. If the length of the specified array is less than the minimum granularity, then it is sorted using the appropriate Arrays.sort method. The algorithm requires a working space no greater than the size of the specified range of the original array. The ForkJoin common pool is used to execute any parallel tasks.
Since:1.8
/** * Sorts the specified range of the specified array of objects according * to the order induced by the specified comparator. The range to be * sorted extends from index {@code fromIndex}, inclusive, to index * {@code toIndex}, exclusive. (If {@code fromIndex==toIndex}, the * range to be sorted is empty.) All elements in the range must be * <i>mutually comparable</i> by the specified comparator (that is, * {@code c.compare(e1, e2)} must not throw a {@code ClassCastException} * for any elements {@code e1} and {@code e2} in the range). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * @implNote The sorting algorithm is a parallel sort-merge that breaks the * array into sub-arrays that are themselves sorted and then merged. When * the sub-array length reaches a minimum granularity, the sub-array is * sorted using the appropriate {@link Arrays#sort(Object[]) Arrays.sort} * method. If the length of the specified array is less than the minimum * granularity, then it is sorted using the appropriate {@link * Arrays#sort(Object[]) Arrays.sort} method. The algorithm requires a working * space no greater than the size of the specified range of the original * array. The {@link ForkJoinPool#commonPool() ForkJoin common pool} is * used to execute any parallel tasks. * * @param <T> the class of the objects to be sorted * @param a the array to be sorted * @param fromIndex the index of the first element (inclusive) to be * sorted * @param toIndex the index of the last element (exclusive) to be sorted * @param cmp the comparator to determine the order of the array. A * {@code null} value indicates that the elements' * {@linkplain Comparable natural ordering} should be used. * @throws IllegalArgumentException if {@code fromIndex > toIndex} or * (optional) if the natural ordering of the array elements is * found to violate the {@link Comparable} contract * @throws ArrayIndexOutOfBoundsException if {@code fromIndex < 0} or * {@code toIndex > a.length} * @throws ClassCastException if the array contains elements that are * not <i>mutually comparable</i> (for example, strings and * integers). * * @since 1.8 */
@SuppressWarnings("unchecked") public static <T> void parallelSort(T[] a, int fromIndex, int toIndex, Comparator<? super T> cmp) { rangeCheck(a.length, fromIndex, toIndex); if (cmp == null) cmp = NaturalOrder.INSTANCE; int n = toIndex - fromIndex, p, g; if (n <= MIN_ARRAY_SORT_GRAN || (p = ForkJoinPool.getCommonPoolParallelism()) == 1) TimSort.sort(a, fromIndex, toIndex, cmp, null, 0, 0); else new ArraysParallelSortHelpers.FJObject.Sorter<T> (null, a, (T[])Array.newInstance(a.getClass().getComponentType(), n), fromIndex, n, 0, ((g = n / (p << 2)) <= MIN_ARRAY_SORT_GRAN) ? MIN_ARRAY_SORT_GRAN : g, cmp).invoke(); } /* * Sorting of complex type arrays. */
Old merge sort implementation can be selected (for compatibility with broken comparators) using a system property. Cannot be a static boolean in the enclosing class due to circular dependencies. To be removed in a future release.
/** * Old merge sort implementation can be selected (for * compatibility with broken comparators) using a system property. * Cannot be a static boolean in the enclosing class due to * circular dependencies. To be removed in a future release. */
static final class LegacyMergeSort { private static final boolean userRequested = java.security.AccessController.doPrivileged( new sun.security.action.GetBooleanAction( "java.util.Arrays.useLegacyMergeSort")).booleanValue(); }
Sorts the specified array of objects into ascending order, according to the natural ordering of its elements. All elements in the array must implement the Comparable interface. Furthermore, all elements in the array must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Implementation note: This implementation is a stable, adaptive, iterative mergesort that requires far fewer than n lg(n) comparisons when the input array is partially sorted, while offering the performance of a traditional mergesort when the input array is randomly ordered. If the input array is nearly sorted, the implementation requires approximately n comparisons. Temporary storage requirements vary from a small constant for nearly sorted input arrays to n/2 object references for randomly ordered input arrays.

The implementation takes equal advantage of ascending and descending order in its input array, and can take advantage of ascending and descending order in different parts of the the same input array. It is well-suited to merging two or more sorted arrays: simply concatenate the arrays and sort the resulting array.

The implementation was adapted from Tim Peters's list sort for Python ( TimSort). It uses techniques from Peter McIlroy's "Optimistic Sorting and Information Theoretic Complexity", in Proceedings of the Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, January 1993.

Params:
  • a – the array to be sorted
Throws:
/** * Sorts the specified array of objects into ascending order, according * to the {@linkplain Comparable natural ordering} of its elements. * All elements in the array must implement the {@link Comparable} * interface. Furthermore, all elements in the array must be * <i>mutually comparable</i> (that is, {@code e1.compareTo(e2)} must * not throw a {@code ClassCastException} for any elements {@code e1} * and {@code e2} in the array). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * <p>Implementation note: This implementation is a stable, adaptive, * iterative mergesort that requires far fewer than n lg(n) comparisons * when the input array is partially sorted, while offering the * performance of a traditional mergesort when the input array is * randomly ordered. If the input array is nearly sorted, the * implementation requires approximately n comparisons. Temporary * storage requirements vary from a small constant for nearly sorted * input arrays to n/2 object references for randomly ordered input * arrays. * * <p>The implementation takes equal advantage of ascending and * descending order in its input array, and can take advantage of * ascending and descending order in different parts of the the same * input array. It is well-suited to merging two or more sorted arrays: * simply concatenate the arrays and sort the resulting array. * * <p>The implementation was adapted from Tim Peters's list sort for Python * (<a href="http://svn.python.org/projects/python/trunk/Objects/listsort.txt"> * TimSort</a>). It uses techniques from Peter McIlroy's "Optimistic * Sorting and Information Theoretic Complexity", in Proceedings of the * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, * January 1993. * * @param a the array to be sorted * @throws ClassCastException if the array contains elements that are not * <i>mutually comparable</i> (for example, strings and integers) * @throws IllegalArgumentException (optional) if the natural * ordering of the array elements is found to violate the * {@link Comparable} contract */
public static void sort(Object[] a) { if (LegacyMergeSort.userRequested) legacyMergeSort(a); else ComparableTimSort.sort(a, 0, a.length, null, 0, 0); }
To be removed in a future release.
/** To be removed in a future release. */
private static void legacyMergeSort(Object[] a) { Object[] aux = a.clone(); mergeSort(aux, a, 0, a.length, 0); }
Sorts the specified range of the specified array of objects into ascending order, according to the natural ordering of its elements. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.) All elements in this range must implement the Comparable interface. Furthermore, all elements in this range must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Implementation note: This implementation is a stable, adaptive, iterative mergesort that requires far fewer than n lg(n) comparisons when the input array is partially sorted, while offering the performance of a traditional mergesort when the input array is randomly ordered. If the input array is nearly sorted, the implementation requires approximately n comparisons. Temporary storage requirements vary from a small constant for nearly sorted input arrays to n/2 object references for randomly ordered input arrays.

The implementation takes equal advantage of ascending and descending order in its input array, and can take advantage of ascending and descending order in different parts of the the same input array. It is well-suited to merging two or more sorted arrays: simply concatenate the arrays and sort the resulting array.

The implementation was adapted from Tim Peters's list sort for Python ( TimSort). It uses techniques from Peter McIlroy's "Optimistic Sorting and Information Theoretic Complexity", in Proceedings of the Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, January 1993.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element (inclusive) to be sorted
  • toIndex – the index of the last element (exclusive) to be sorted
Throws:
/** * Sorts the specified range of the specified array of objects into * ascending order, according to the * {@linkplain Comparable natural ordering} of its * elements. The range to be sorted extends from index * {@code fromIndex}, inclusive, to index {@code toIndex}, exclusive. * (If {@code fromIndex==toIndex}, the range to be sorted is empty.) All * elements in this range must implement the {@link Comparable} * interface. Furthermore, all elements in this range must be <i>mutually * comparable</i> (that is, {@code e1.compareTo(e2)} must not throw a * {@code ClassCastException} for any elements {@code e1} and * {@code e2} in the array). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * <p>Implementation note: This implementation is a stable, adaptive, * iterative mergesort that requires far fewer than n lg(n) comparisons * when the input array is partially sorted, while offering the * performance of a traditional mergesort when the input array is * randomly ordered. If the input array is nearly sorted, the * implementation requires approximately n comparisons. Temporary * storage requirements vary from a small constant for nearly sorted * input arrays to n/2 object references for randomly ordered input * arrays. * * <p>The implementation takes equal advantage of ascending and * descending order in its input array, and can take advantage of * ascending and descending order in different parts of the the same * input array. It is well-suited to merging two or more sorted arrays: * simply concatenate the arrays and sort the resulting array. * * <p>The implementation was adapted from Tim Peters's list sort for Python * (<a href="http://svn.python.org/projects/python/trunk/Objects/listsort.txt"> * TimSort</a>). It uses techniques from Peter McIlroy's "Optimistic * Sorting and Information Theoretic Complexity", in Proceedings of the * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, * January 1993. * * @param a the array to be sorted * @param fromIndex the index of the first element (inclusive) to be * sorted * @param toIndex the index of the last element (exclusive) to be sorted * @throws IllegalArgumentException if {@code fromIndex > toIndex} or * (optional) if the natural ordering of the array elements is * found to violate the {@link Comparable} contract * @throws ArrayIndexOutOfBoundsException if {@code fromIndex < 0} or * {@code toIndex > a.length} * @throws ClassCastException if the array contains elements that are * not <i>mutually comparable</i> (for example, strings and * integers). */
public static void sort(Object[] a, int fromIndex, int toIndex) { rangeCheck(a.length, fromIndex, toIndex); if (LegacyMergeSort.userRequested) legacyMergeSort(a, fromIndex, toIndex); else ComparableTimSort.sort(a, fromIndex, toIndex, null, 0, 0); }
To be removed in a future release.
/** To be removed in a future release. */
private static void legacyMergeSort(Object[] a, int fromIndex, int toIndex) { Object[] aux = copyOfRange(a, fromIndex, toIndex); mergeSort(aux, a, fromIndex, toIndex, -fromIndex); }
Tuning parameter: list size at or below which insertion sort will be used in preference to mergesort. To be removed in a future release.
/** * Tuning parameter: list size at or below which insertion sort will be * used in preference to mergesort. * To be removed in a future release. */
private static final int INSERTIONSORT_THRESHOLD = 7;
Src is the source array that starts at index 0 Dest is the (possibly larger) array destination with a possible offset low is the index in dest to start sorting high is the end index in dest to end sorting off is the offset to generate corresponding low, high in src To be removed in a future release.
/** * Src is the source array that starts at index 0 * Dest is the (possibly larger) array destination with a possible offset * low is the index in dest to start sorting * high is the end index in dest to end sorting * off is the offset to generate corresponding low, high in src * To be removed in a future release. */
@SuppressWarnings({"unchecked", "rawtypes"}) private static void mergeSort(Object[] src, Object[] dest, int low, int high, int off) { int length = high - low; // Insertion sort on smallest arrays if (length < INSERTIONSORT_THRESHOLD) { for (int i=low; i<high; i++) for (int j=i; j>low && ((Comparable) dest[j-1]).compareTo(dest[j])>0; j--) swap(dest, j, j-1); return; } // Recursively sort halves of dest into src int destLow = low; int destHigh = high; low += off; high += off; int mid = (low + high) >>> 1; mergeSort(dest, src, low, mid, -off); mergeSort(dest, src, mid, high, -off); // If list is already sorted, just copy from src to dest. This is an // optimization that results in faster sorts for nearly ordered lists. if (((Comparable)src[mid-1]).compareTo(src[mid]) <= 0) { System.arraycopy(src, low, dest, destLow, length); return; } // Merge sorted halves (now in src) into dest for(int i = destLow, p = low, q = mid; i < destHigh; i++) { if (q >= high || p < mid && ((Comparable)src[p]).compareTo(src[q])<=0) dest[i] = src[p++]; else dest[i] = src[q++]; } }
Swaps x[a] with x[b].
/** * Swaps x[a] with x[b]. */
private static void swap(Object[] x, int a, int b) { Object t = x[a]; x[a] = x[b]; x[b] = t; }
Sorts the specified array of objects according to the order induced by the specified comparator. All elements in the array must be mutually comparable by the specified comparator (that is, c.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Implementation note: This implementation is a stable, adaptive, iterative mergesort that requires far fewer than n lg(n) comparisons when the input array is partially sorted, while offering the performance of a traditional mergesort when the input array is randomly ordered. If the input array is nearly sorted, the implementation requires approximately n comparisons. Temporary storage requirements vary from a small constant for nearly sorted input arrays to n/2 object references for randomly ordered input arrays.

The implementation takes equal advantage of ascending and descending order in its input array, and can take advantage of ascending and descending order in different parts of the the same input array. It is well-suited to merging two or more sorted arrays: simply concatenate the arrays and sort the resulting array.

The implementation was adapted from Tim Peters's list sort for Python ( TimSort). It uses techniques from Peter McIlroy's "Optimistic Sorting and Information Theoretic Complexity", in Proceedings of the Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, January 1993.

Params:
  • a – the array to be sorted
  • c – the comparator to determine the order of the array. A null value indicates that the elements' natural ordering should be used.
Type parameters:
  • <T> – the class of the objects to be sorted
Throws:
/** * Sorts the specified array of objects according to the order induced by * the specified comparator. All elements in the array must be * <i>mutually comparable</i> by the specified comparator (that is, * {@code c.compare(e1, e2)} must not throw a {@code ClassCastException} * for any elements {@code e1} and {@code e2} in the array). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * <p>Implementation note: This implementation is a stable, adaptive, * iterative mergesort that requires far fewer than n lg(n) comparisons * when the input array is partially sorted, while offering the * performance of a traditional mergesort when the input array is * randomly ordered. If the input array is nearly sorted, the * implementation requires approximately n comparisons. Temporary * storage requirements vary from a small constant for nearly sorted * input arrays to n/2 object references for randomly ordered input * arrays. * * <p>The implementation takes equal advantage of ascending and * descending order in its input array, and can take advantage of * ascending and descending order in different parts of the the same * input array. It is well-suited to merging two or more sorted arrays: * simply concatenate the arrays and sort the resulting array. * * <p>The implementation was adapted from Tim Peters's list sort for Python * (<a href="http://svn.python.org/projects/python/trunk/Objects/listsort.txt"> * TimSort</a>). It uses techniques from Peter McIlroy's "Optimistic * Sorting and Information Theoretic Complexity", in Proceedings of the * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, * January 1993. * * @param <T> the class of the objects to be sorted * @param a the array to be sorted * @param c the comparator to determine the order of the array. A * {@code null} value indicates that the elements' * {@linkplain Comparable natural ordering} should be used. * @throws ClassCastException if the array contains elements that are * not <i>mutually comparable</i> using the specified comparator * @throws IllegalArgumentException (optional) if the comparator is * found to violate the {@link Comparator} contract */
public static <T> void sort(T[] a, Comparator<? super T> c) { if (c == null) { sort(a); } else { if (LegacyMergeSort.userRequested) legacyMergeSort(a, c); else TimSort.sort(a, 0, a.length, c, null, 0, 0); } }
To be removed in a future release.
/** To be removed in a future release. */
private static <T> void legacyMergeSort(T[] a, Comparator<? super T> c) { T[] aux = a.clone(); if (c==null) mergeSort(aux, a, 0, a.length, 0); else mergeSort(aux, a, 0, a.length, 0, c); }
Sorts the specified range of the specified array of objects according to the order induced by the specified comparator. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.) All elements in the range must be mutually comparable by the specified comparator (that is, c.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the range).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Implementation note: This implementation is a stable, adaptive, iterative mergesort that requires far fewer than n lg(n) comparisons when the input array is partially sorted, while offering the performance of a traditional mergesort when the input array is randomly ordered. If the input array is nearly sorted, the implementation requires approximately n comparisons. Temporary storage requirements vary from a small constant for nearly sorted input arrays to n/2 object references for randomly ordered input arrays.

The implementation takes equal advantage of ascending and descending order in its input array, and can take advantage of ascending and descending order in different parts of the the same input array. It is well-suited to merging two or more sorted arrays: simply concatenate the arrays and sort the resulting array.

The implementation was adapted from Tim Peters's list sort for Python ( TimSort). It uses techniques from Peter McIlroy's "Optimistic Sorting and Information Theoretic Complexity", in Proceedings of the Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, January 1993.

Params:
  • a – the array to be sorted
  • fromIndex – the index of the first element (inclusive) to be sorted
  • toIndex – the index of the last element (exclusive) to be sorted
  • c – the comparator to determine the order of the array. A null value indicates that the elements' natural ordering should be used.
Type parameters:
  • <T> – the class of the objects to be sorted
Throws:
/** * Sorts the specified range of the specified array of objects according * to the order induced by the specified comparator. The range to be * sorted extends from index {@code fromIndex}, inclusive, to index * {@code toIndex}, exclusive. (If {@code fromIndex==toIndex}, the * range to be sorted is empty.) All elements in the range must be * <i>mutually comparable</i> by the specified comparator (that is, * {@code c.compare(e1, e2)} must not throw a {@code ClassCastException} * for any elements {@code e1} and {@code e2} in the range). * * <p>This sort is guaranteed to be <i>stable</i>: equal elements will * not be reordered as a result of the sort. * * <p>Implementation note: This implementation is a stable, adaptive, * iterative mergesort that requires far fewer than n lg(n) comparisons * when the input array is partially sorted, while offering the * performance of a traditional mergesort when the input array is * randomly ordered. If the input array is nearly sorted, the * implementation requires approximately n comparisons. Temporary * storage requirements vary from a small constant for nearly sorted * input arrays to n/2 object references for randomly ordered input * arrays. * * <p>The implementation takes equal advantage of ascending and * descending order in its input array, and can take advantage of * ascending and descending order in different parts of the the same * input array. It is well-suited to merging two or more sorted arrays: * simply concatenate the arrays and sort the resulting array. * * <p>The implementation was adapted from Tim Peters's list sort for Python * (<a href="http://svn.python.org/projects/python/trunk/Objects/listsort.txt"> * TimSort</a>). It uses techniques from Peter McIlroy's "Optimistic * Sorting and Information Theoretic Complexity", in Proceedings of the * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474, * January 1993. * * @param <T> the class of the objects to be sorted * @param a the array to be sorted * @param fromIndex the index of the first element (inclusive) to be * sorted * @param toIndex the index of the last element (exclusive) to be sorted * @param c the comparator to determine the order of the array. A * {@code null} value indicates that the elements' * {@linkplain Comparable natural ordering} should be used. * @throws ClassCastException if the array contains elements that are not * <i>mutually comparable</i> using the specified comparator. * @throws IllegalArgumentException if {@code fromIndex > toIndex} or * (optional) if the comparator is found to violate the * {@link Comparator} contract * @throws ArrayIndexOutOfBoundsException if {@code fromIndex < 0} or * {@code toIndex > a.length} */
public static <T> void sort(T[] a, int fromIndex, int toIndex, Comparator<? super T> c) { if (c == null) { sort(a, fromIndex, toIndex); } else { rangeCheck(a.length, fromIndex, toIndex); if (LegacyMergeSort.userRequested) legacyMergeSort(a, fromIndex, toIndex, c); else TimSort.sort(a, fromIndex, toIndex, c, null, 0, 0); } }
To be removed in a future release.
/** To be removed in a future release. */
private static <T> void legacyMergeSort(T[] a, int fromIndex, int toIndex, Comparator<? super T> c) { T[] aux = copyOfRange(a, fromIndex, toIndex); if (c==null) mergeSort(aux, a, fromIndex, toIndex, -fromIndex); else mergeSort(aux, a, fromIndex, toIndex, -fromIndex, c); }
Src is the source array that starts at index 0 Dest is the (possibly larger) array destination with a possible offset low is the index in dest to start sorting high is the end index in dest to end sorting off is the offset into src corresponding to low in dest To be removed in a future release.
/** * Src is the source array that starts at index 0 * Dest is the (possibly larger) array destination with a possible offset * low is the index in dest to start sorting * high is the end index in dest to end sorting * off is the offset into src corresponding to low in dest * To be removed in a future release. */
@SuppressWarnings({"rawtypes", "unchecked"}) private static void mergeSort(Object[] src, Object[] dest, int low, int high, int off, Comparator c) { int length = high - low; // Insertion sort on smallest arrays if (length < INSERTIONSORT_THRESHOLD) { for (int i=low; i<high; i++) for (int j=i; j>low && c.compare(dest[j-1], dest[j])>0; j--) swap(dest, j, j-1); return; } // Recursively sort halves of dest into src int destLow = low; int destHigh = high; low += off; high += off; int mid = (low + high) >>> 1; mergeSort(dest, src, low, mid, -off, c); mergeSort(dest, src, mid, high, -off, c); // If list is already sorted, just copy from src to dest. This is an // optimization that results in faster sorts for nearly ordered lists. if (c.compare(src[mid-1], src[mid]) <= 0) { System.arraycopy(src, low, dest, destLow, length); return; } // Merge sorted halves (now in src) into dest for(int i = destLow, p = low, q = mid; i < destHigh; i++) { if (q >= high || p < mid && c.compare(src[p], src[q]) <= 0) dest[i] = src[p++]; else dest[i] = src[q++]; } } // Parallel prefix
Cumulates, in parallel, each element of the given array in place, using the supplied function. For example if the array initially holds [2, 1, 0, 3] and the operation performs addition, then upon return the array holds [2, 3, 3, 6]. Parallel prefix computation is usually more efficient than sequential loops for large arrays.
Params:
  • array – the array, which is modified in-place by this method
  • op – a side-effect-free, associative function to perform the cumulation
Type parameters:
  • <T> – the class of the objects in the array
Throws:
Since:1.8
/** * Cumulates, in parallel, each element of the given array in place, * using the supplied function. For example if the array initially * holds {@code [2, 1, 0, 3]} and the operation performs addition, * then upon return the array holds {@code [2, 3, 3, 6]}. * Parallel prefix computation is usually more efficient than * sequential loops for large arrays. * * @param <T> the class of the objects in the array * @param array the array, which is modified in-place by this method * @param op a side-effect-free, associative function to perform the * cumulation * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static <T> void parallelPrefix(T[] array, BinaryOperator<T> op) { Objects.requireNonNull(op); if (array.length > 0) new ArrayPrefixHelpers.CumulateTask<> (null, op, array, 0, array.length).invoke(); }
Performs parallelPrefix(Object[], BinaryOperator<Object>) for the given subrange of the array.
Params:
  • array – the array
  • fromIndex – the index of the first element, inclusive
  • toIndex – the index of the last element, exclusive
  • op – a side-effect-free, associative function to perform the cumulation
Type parameters:
  • <T> – the class of the objects in the array
Throws:
Since:1.8
/** * Performs {@link #parallelPrefix(Object[], BinaryOperator)} * for the given subrange of the array. * * @param <T> the class of the objects in the array * @param array the array * @param fromIndex the index of the first element, inclusive * @param toIndex the index of the last element, exclusive * @param op a side-effect-free, associative function to perform the * cumulation * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > array.length} * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static <T> void parallelPrefix(T[] array, int fromIndex, int toIndex, BinaryOperator<T> op) { Objects.requireNonNull(op); rangeCheck(array.length, fromIndex, toIndex); if (fromIndex < toIndex) new ArrayPrefixHelpers.CumulateTask<> (null, op, array, fromIndex, toIndex).invoke(); }
Cumulates, in parallel, each element of the given array in place, using the supplied function. For example if the array initially holds [2, 1, 0, 3] and the operation performs addition, then upon return the array holds [2, 3, 3, 6]. Parallel prefix computation is usually more efficient than sequential loops for large arrays.
Params:
  • array – the array, which is modified in-place by this method
  • op – a side-effect-free, associative function to perform the cumulation
Throws:
Since:1.8
/** * Cumulates, in parallel, each element of the given array in place, * using the supplied function. For example if the array initially * holds {@code [2, 1, 0, 3]} and the operation performs addition, * then upon return the array holds {@code [2, 3, 3, 6]}. * Parallel prefix computation is usually more efficient than * sequential loops for large arrays. * * @param array the array, which is modified in-place by this method * @param op a side-effect-free, associative function to perform the * cumulation * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static void parallelPrefix(long[] array, LongBinaryOperator op) { Objects.requireNonNull(op); if (array.length > 0) new ArrayPrefixHelpers.LongCumulateTask (null, op, array, 0, array.length).invoke(); }
Performs parallelPrefix(long[], LongBinaryOperator) for the given subrange of the array.
Params:
  • array – the array
  • fromIndex – the index of the first element, inclusive
  • toIndex – the index of the last element, exclusive
  • op – a side-effect-free, associative function to perform the cumulation
Throws:
Since:1.8
/** * Performs {@link #parallelPrefix(long[], LongBinaryOperator)} * for the given subrange of the array. * * @param array the array * @param fromIndex the index of the first element, inclusive * @param toIndex the index of the last element, exclusive * @param op a side-effect-free, associative function to perform the * cumulation * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > array.length} * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static void parallelPrefix(long[] array, int fromIndex, int toIndex, LongBinaryOperator op) { Objects.requireNonNull(op); rangeCheck(array.length, fromIndex, toIndex); if (fromIndex < toIndex) new ArrayPrefixHelpers.LongCumulateTask (null, op, array, fromIndex, toIndex).invoke(); }
Cumulates, in parallel, each element of the given array in place, using the supplied function. For example if the array initially holds [2.0, 1.0, 0.0, 3.0] and the operation performs addition, then upon return the array holds [2.0, 3.0, 3.0, 6.0]. Parallel prefix computation is usually more efficient than sequential loops for large arrays.

Because floating-point operations may not be strictly associative, the returned result may not be identical to the value that would be obtained if the operation was performed sequentially.

Params:
  • array – the array, which is modified in-place by this method
  • op – a side-effect-free function to perform the cumulation
Throws:
Since:1.8
/** * Cumulates, in parallel, each element of the given array in place, * using the supplied function. For example if the array initially * holds {@code [2.0, 1.0, 0.0, 3.0]} and the operation performs addition, * then upon return the array holds {@code [2.0, 3.0, 3.0, 6.0]}. * Parallel prefix computation is usually more efficient than * sequential loops for large arrays. * * <p> Because floating-point operations may not be strictly associative, * the returned result may not be identical to the value that would be * obtained if the operation was performed sequentially. * * @param array the array, which is modified in-place by this method * @param op a side-effect-free function to perform the cumulation * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static void parallelPrefix(double[] array, DoubleBinaryOperator op) { Objects.requireNonNull(op); if (array.length > 0) new ArrayPrefixHelpers.DoubleCumulateTask (null, op, array, 0, array.length).invoke(); }
Performs parallelPrefix(double[], DoubleBinaryOperator) for the given subrange of the array.
Params:
  • array – the array
  • fromIndex – the index of the first element, inclusive
  • toIndex – the index of the last element, exclusive
  • op – a side-effect-free, associative function to perform the cumulation
Throws:
Since:1.8
/** * Performs {@link #parallelPrefix(double[], DoubleBinaryOperator)} * for the given subrange of the array. * * @param array the array * @param fromIndex the index of the first element, inclusive * @param toIndex the index of the last element, exclusive * @param op a side-effect-free, associative function to perform the * cumulation * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > array.length} * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static void parallelPrefix(double[] array, int fromIndex, int toIndex, DoubleBinaryOperator op) { Objects.requireNonNull(op); rangeCheck(array.length, fromIndex, toIndex); if (fromIndex < toIndex) new ArrayPrefixHelpers.DoubleCumulateTask (null, op, array, fromIndex, toIndex).invoke(); }
Cumulates, in parallel, each element of the given array in place, using the supplied function. For example if the array initially holds [2, 1, 0, 3] and the operation performs addition, then upon return the array holds [2, 3, 3, 6]. Parallel prefix computation is usually more efficient than sequential loops for large arrays.
Params:
  • array – the array, which is modified in-place by this method
  • op – a side-effect-free, associative function to perform the cumulation
Throws:
Since:1.8
/** * Cumulates, in parallel, each element of the given array in place, * using the supplied function. For example if the array initially * holds {@code [2, 1, 0, 3]} and the operation performs addition, * then upon return the array holds {@code [2, 3, 3, 6]}. * Parallel prefix computation is usually more efficient than * sequential loops for large arrays. * * @param array the array, which is modified in-place by this method * @param op a side-effect-free, associative function to perform the * cumulation * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static void parallelPrefix(int[] array, IntBinaryOperator op) { Objects.requireNonNull(op); if (array.length > 0) new ArrayPrefixHelpers.IntCumulateTask (null, op, array, 0, array.length).invoke(); }
Performs parallelPrefix(int[], IntBinaryOperator) for the given subrange of the array.
Params:
  • array – the array
  • fromIndex – the index of the first element, inclusive
  • toIndex – the index of the last element, exclusive
  • op – a side-effect-free, associative function to perform the cumulation
Throws:
Since:1.8
/** * Performs {@link #parallelPrefix(int[], IntBinaryOperator)} * for the given subrange of the array. * * @param array the array * @param fromIndex the index of the first element, inclusive * @param toIndex the index of the last element, exclusive * @param op a side-effect-free, associative function to perform the * cumulation * @throws IllegalArgumentException if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0} or {@code toIndex > array.length} * @throws NullPointerException if the specified array or function is null * @since 1.8 */
public static void parallelPrefix(int[] array, int fromIndex, int toIndex, IntBinaryOperator op) { Objects.requireNonNull(op); rangeCheck(array.length, fromIndex, toIndex); if (fromIndex < toIndex) new ArrayPrefixHelpers.IntCumulateTask (null, op, array, fromIndex, toIndex).invoke(); } // Searching
Searches the specified array of longs for the specified value using the binary search algorithm. The array must be sorted (as by the sort(long[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array of longs for the specified value using the * binary search algorithm. The array must be sorted (as * by the {@link #sort(long[])} method) prior to making this call. If it * is not sorted, the results are undefined. If the array contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. */
public static int binarySearch(long[] a, long key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array of longs for the specified value using the binary search algorithm. The range must be sorted (as by the sort(long[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array of longs for the specified value using the * binary search algorithm. * The range must be sorted (as * by the {@link #sort(long[], int, int)} method) * prior to making this call. If it * is not sorted, the results are undefined. If the range contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(long[] a, int fromIndex, int toIndex, long key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(long[] a, int fromIndex, int toIndex, long key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; long midVal = a[mid]; if (midVal < key) low = mid + 1; else if (midVal > key) high = mid - 1; else return mid; // key found } return -(low + 1); // key not found. }
Searches the specified array of ints for the specified value using the binary search algorithm. The array must be sorted (as by the sort(int[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array of ints for the specified value using the * binary search algorithm. The array must be sorted (as * by the {@link #sort(int[])} method) prior to making this call. If it * is not sorted, the results are undefined. If the array contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. */
public static int binarySearch(int[] a, int key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array of ints for the specified value using the binary search algorithm. The range must be sorted (as by the sort(int[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array of ints for the specified value using the * binary search algorithm. * The range must be sorted (as * by the {@link #sort(int[], int, int)} method) * prior to making this call. If it * is not sorted, the results are undefined. If the range contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(int[] a, int fromIndex, int toIndex, int key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(int[] a, int fromIndex, int toIndex, int key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; int midVal = a[mid]; if (midVal < key) low = mid + 1; else if (midVal > key) high = mid - 1; else return mid; // key found } return -(low + 1); // key not found. }
Searches the specified array of shorts for the specified value using the binary search algorithm. The array must be sorted (as by the sort(short[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array of shorts for the specified value using * the binary search algorithm. The array must be sorted * (as by the {@link #sort(short[])} method) prior to making this call. If * it is not sorted, the results are undefined. If the array contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. */
public static int binarySearch(short[] a, short key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array of shorts for the specified value using the binary search algorithm. The range must be sorted (as by the sort(short[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array of shorts for the specified value using * the binary search algorithm. * The range must be sorted * (as by the {@link #sort(short[], int, int)} method) * prior to making this call. If * it is not sorted, the results are undefined. If the range contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(short[] a, int fromIndex, int toIndex, short key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(short[] a, int fromIndex, int toIndex, short key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; short midVal = a[mid]; if (midVal < key) low = mid + 1; else if (midVal > key) high = mid - 1; else return mid; // key found } return -(low + 1); // key not found. }
Searches the specified array of chars for the specified value using the binary search algorithm. The array must be sorted (as by the sort(char[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array of chars for the specified value using the * binary search algorithm. The array must be sorted (as * by the {@link #sort(char[])} method) prior to making this call. If it * is not sorted, the results are undefined. If the array contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. */
public static int binarySearch(char[] a, char key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array of chars for the specified value using the binary search algorithm. The range must be sorted (as by the sort(char[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array of chars for the specified value using the * binary search algorithm. * The range must be sorted (as * by the {@link #sort(char[], int, int)} method) * prior to making this call. If it * is not sorted, the results are undefined. If the range contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(char[] a, int fromIndex, int toIndex, char key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(char[] a, int fromIndex, int toIndex, char key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; char midVal = a[mid]; if (midVal < key) low = mid + 1; else if (midVal > key) high = mid - 1; else return mid; // key found } return -(low + 1); // key not found. }
Searches the specified array of bytes for the specified value using the binary search algorithm. The array must be sorted (as by the sort(byte[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array of bytes for the specified value using the * binary search algorithm. The array must be sorted (as * by the {@link #sort(byte[])} method) prior to making this call. If it * is not sorted, the results are undefined. If the array contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. */
public static int binarySearch(byte[] a, byte key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array of bytes for the specified value using the binary search algorithm. The range must be sorted (as by the sort(byte[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array of bytes for the specified value using the * binary search algorithm. * The range must be sorted (as * by the {@link #sort(byte[], int, int)} method) * prior to making this call. If it * is not sorted, the results are undefined. If the range contains * multiple elements with the specified value, there is no guarantee which * one will be found. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(byte[] a, int fromIndex, int toIndex, byte key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(byte[] a, int fromIndex, int toIndex, byte key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; byte midVal = a[mid]; if (midVal < key) low = mid + 1; else if (midVal > key) high = mid - 1; else return mid; // key found } return -(low + 1); // key not found. }
Searches the specified array of doubles for the specified value using the binary search algorithm. The array must be sorted (as by the sort(double[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array of doubles for the specified value using * the binary search algorithm. The array must be sorted * (as by the {@link #sort(double[])} method) prior to making this call. * If it is not sorted, the results are undefined. If the array contains * multiple elements with the specified value, there is no guarantee which * one will be found. This method considers all NaN values to be * equivalent and equal. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. */
public static int binarySearch(double[] a, double key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array of doubles for the specified value using the binary search algorithm. The range must be sorted (as by the sort(double[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array of doubles for the specified value using * the binary search algorithm. * The range must be sorted * (as by the {@link #sort(double[], int, int)} method) * prior to making this call. * If it is not sorted, the results are undefined. If the range contains * multiple elements with the specified value, there is no guarantee which * one will be found. This method considers all NaN values to be * equivalent and equal. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(double[] a, int fromIndex, int toIndex, double key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(double[] a, int fromIndex, int toIndex, double key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; double midVal = a[mid]; if (midVal < key) low = mid + 1; // Neither val is NaN, thisVal is smaller else if (midVal > key) high = mid - 1; // Neither val is NaN, thisVal is larger else { long midBits = Double.doubleToLongBits(midVal); long keyBits = Double.doubleToLongBits(key); if (midBits == keyBits) // Values are equal return mid; // Key found else if (midBits < keyBits) // (-0.0, 0.0) or (!NaN, NaN) low = mid + 1; else // (0.0, -0.0) or (NaN, !NaN) high = mid - 1; } } return -(low + 1); // key not found. }
Searches the specified array of floats for the specified value using the binary search algorithm. The array must be sorted (as by the sort(float[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array of floats for the specified value using * the binary search algorithm. The array must be sorted * (as by the {@link #sort(float[])} method) prior to making this call. If * it is not sorted, the results are undefined. If the array contains * multiple elements with the specified value, there is no guarantee which * one will be found. This method considers all NaN values to be * equivalent and equal. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. */
public static int binarySearch(float[] a, float key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array of floats for the specified value using the binary search algorithm. The range must be sorted (as by the sort(float[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array of floats for the specified value using * the binary search algorithm. * The range must be sorted * (as by the {@link #sort(float[], int, int)} method) * prior to making this call. If * it is not sorted, the results are undefined. If the range contains * multiple elements with the specified value, there is no guarantee which * one will be found. This method considers all NaN values to be * equivalent and equal. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(float[] a, int fromIndex, int toIndex, float key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(float[] a, int fromIndex, int toIndex, float key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; float midVal = a[mid]; if (midVal < key) low = mid + 1; // Neither val is NaN, thisVal is smaller else if (midVal > key) high = mid - 1; // Neither val is NaN, thisVal is larger else { int midBits = Float.floatToIntBits(midVal); int keyBits = Float.floatToIntBits(key); if (midBits == keyBits) // Values are equal return mid; // Key found else if (midBits < keyBits) // (-0.0, 0.0) or (!NaN, NaN) low = mid + 1; else // (0.0, -0.0) or (NaN, !NaN) high = mid - 1; } } return -(low + 1); // key not found. }
Searches the specified array for the specified object using the binary search algorithm. The array must be sorted into ascending order according to the natural ordering of its elements (as by the sort(Object[]) method) prior to making this call. If it is not sorted, the results are undefined. (If the array contains elements that are not mutually comparable (for example, strings and integers), it cannot be sorted according to the natural ordering of its elements, hence results are undefined.) If the array contains multiple elements equal to the specified object, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array for the specified object using the binary * search algorithm. The array must be sorted into ascending order * according to the * {@linkplain Comparable natural ordering} * of its elements (as by the * {@link #sort(Object[])} method) prior to making this call. * If it is not sorted, the results are undefined. * (If the array contains elements that are not mutually comparable (for * example, strings and integers), it <i>cannot</i> be sorted according * to the natural ordering of its elements, hence results are undefined.) * If the array contains multiple * elements equal to the specified object, there is no guarantee which * one will be found. * * @param a the array to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws ClassCastException if the search key is not comparable to the * elements of the array. */
public static int binarySearch(Object[] a, Object key) { return binarySearch0(a, 0, a.length, key); }
Searches a range of the specified array for the specified object using the binary search algorithm. The range must be sorted into ascending order according to the natural ordering of its elements (as by the sort(Object[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. (If the range contains elements that are not mutually comparable (for example, strings and integers), it cannot be sorted according to the natural ordering of its elements, hence results are undefined.) If the range contains multiple elements equal to the specified object, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array for the specified object using the binary * search algorithm. * The range must be sorted into ascending order * according to the * {@linkplain Comparable natural ordering} * of its elements (as by the * {@link #sort(Object[], int, int)} method) prior to making this * call. If it is not sorted, the results are undefined. * (If the range contains elements that are not mutually comparable (for * example, strings and integers), it <i>cannot</i> be sorted according * to the natural ordering of its elements, hence results are undefined.) * If the range contains multiple * elements equal to the specified object, there is no guarantee which * one will be found. * * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws ClassCastException if the search key is not comparable to the * elements of the array within the specified range. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static int binarySearch(Object[] a, int fromIndex, int toIndex, Object key) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key); } // Like public version, but without range checks. private static int binarySearch0(Object[] a, int fromIndex, int toIndex, Object key) { int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; @SuppressWarnings("rawtypes") Comparable midVal = (Comparable)a[mid]; @SuppressWarnings("unchecked") int cmp = midVal.compareTo(key); if (cmp < 0) low = mid + 1; else if (cmp > 0) high = mid - 1; else return mid; // key found } return -(low + 1); // key not found. }
Searches the specified array for the specified object using the binary search algorithm. The array must be sorted into ascending order according to the specified comparator (as by the sort(T[], Comparator) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements equal to the specified object, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • key – the value to be searched for
  • c – the comparator by which the array is ordered. A null value indicates that the elements' natural ordering should be used.
Type parameters:
  • <T> – the class of the objects in the array
Throws:
  • ClassCastException – if the array contains elements that are not mutually comparable using the specified comparator, or the search key is not comparable to the elements of the array using this comparator.
Returns:index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
/** * Searches the specified array for the specified object using the binary * search algorithm. The array must be sorted into ascending order * according to the specified comparator (as by the * {@link #sort(Object[], Comparator) sort(T[], Comparator)} * method) prior to making this call. If it is * not sorted, the results are undefined. * If the array contains multiple * elements equal to the specified object, there is no guarantee which one * will be found. * * @param <T> the class of the objects in the array * @param a the array to be searched * @param key the value to be searched for * @param c the comparator by which the array is ordered. A * <tt>null</tt> value indicates that the elements' * {@linkplain Comparable natural ordering} should be used. * @return index of the search key, if it is contained in the array; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element greater than the key, or <tt>a.length</tt> if all * elements in the array are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws ClassCastException if the array contains elements that are not * <i>mutually comparable</i> using the specified comparator, * or the search key is not comparable to the * elements of the array using this comparator. */
public static <T> int binarySearch(T[] a, T key, Comparator<? super T> c) { return binarySearch0(a, 0, a.length, key, c); }
Searches a range of the specified array for the specified object using the binary search algorithm. The range must be sorted into ascending order according to the specified comparator (as by the sort(T[], int, int, Comparator) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements equal to the specified object, there is no guarantee which one will be found.
Params:
  • a – the array to be searched
  • fromIndex – the index of the first element (inclusive) to be searched
  • toIndex – the index of the last element (exclusive) to be searched
  • key – the value to be searched for
  • c – the comparator by which the array is ordered. A null value indicates that the elements' natural ordering should be used.
Type parameters:
  • <T> – the class of the objects in the array
Throws:
Returns:index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.
Since:1.6
/** * Searches a range of * the specified array for the specified object using the binary * search algorithm. * The range must be sorted into ascending order * according to the specified comparator (as by the * {@link #sort(Object[], int, int, Comparator) * sort(T[], int, int, Comparator)} * method) prior to making this call. * If it is not sorted, the results are undefined. * If the range contains multiple elements equal to the specified object, * there is no guarantee which one will be found. * * @param <T> the class of the objects in the array * @param a the array to be searched * @param fromIndex the index of the first element (inclusive) to be * searched * @param toIndex the index of the last element (exclusive) to be searched * @param key the value to be searched for * @param c the comparator by which the array is ordered. A * <tt>null</tt> value indicates that the elements' * {@linkplain Comparable natural ordering} should be used. * @return index of the search key, if it is contained in the array * within the specified range; * otherwise, <tt>(-(<i>insertion point</i>) - 1)</tt>. The * <i>insertion point</i> is defined as the point at which the * key would be inserted into the array: the index of the first * element in the range greater than the key, * or <tt>toIndex</tt> if all * elements in the range are less than the specified key. Note * that this guarantees that the return value will be &gt;= 0 if * and only if the key is found. * @throws ClassCastException if the range contains elements that are not * <i>mutually comparable</i> using the specified comparator, * or the search key is not comparable to the * elements in the range using this comparator. * @throws IllegalArgumentException * if {@code fromIndex > toIndex} * @throws ArrayIndexOutOfBoundsException * if {@code fromIndex < 0 or toIndex > a.length} * @since 1.6 */
public static <T> int binarySearch(T[] a, int fromIndex, int toIndex, T key, Comparator<? super T> c) { rangeCheck(a.length, fromIndex, toIndex); return binarySearch0(a, fromIndex, toIndex, key, c); } // Like public version, but without range checks. private static <T> int binarySearch0(T[] a, int fromIndex, int toIndex, T key, Comparator<? super T> c) { if (c == null) { return binarySearch0(a, fromIndex, toIndex, key); } int low = fromIndex; int high = toIndex - 1; while (low <= high) { int mid = (low + high) >>> 1; T midVal = a[mid]; int cmp = c.compare(midVal, key); if (cmp < 0) low = mid + 1; else if (cmp > 0) high = mid - 1; else return mid; // key found } return -(low + 1); // key not found. } // Equality Testing
Returns true if the two specified arrays of longs are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of longs are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal */
public static boolean equals(long[] a, long[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (a[i] != a2[i]) return false; return true; }
Returns true if the two specified arrays of ints are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of ints are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal */
public static boolean equals(int[] a, int[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (a[i] != a2[i]) return false; return true; }
Returns true if the two specified arrays of shorts are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of shorts are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal */
public static boolean equals(short[] a, short a2[]) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (a[i] != a2[i]) return false; return true; }
Returns true if the two specified arrays of chars are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of chars are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal */
public static boolean equals(char[] a, char[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (a[i] != a2[i]) return false; return true; }
Returns true if the two specified arrays of bytes are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of bytes are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal */
public static boolean equals(byte[] a, byte[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (a[i] != a2[i]) return false; return true; }
Returns true if the two specified arrays of booleans are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of booleans are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal */
public static boolean equals(boolean[] a, boolean[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (a[i] != a2[i]) return false; return true; }
Returns true if the two specified arrays of doubles are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Two doubles d1 and d2 are considered equal if:

    new Double(d1).equals(new Double(d2))
(Unlike the == operator, this method considers NaN equals to itself, and 0.0d unequal to -0.0d.)
Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
See Also:
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of doubles are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * Two doubles <tt>d1</tt> and <tt>d2</tt> are considered equal if: * <pre> <tt>new Double(d1).equals(new Double(d2))</tt></pre> * (Unlike the <tt>==</tt> operator, this method considers * <tt>NaN</tt> equals to itself, and 0.0d unequal to -0.0d.) * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal * @see Double#equals(Object) */
public static boolean equals(double[] a, double[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (Double.doubleToLongBits(a[i])!=Double.doubleToLongBits(a2[i])) return false; return true; }
Returns true if the two specified arrays of floats are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Two floats f1 and f2 are considered equal if:

    new Float(f1).equals(new Float(f2))
(Unlike the == operator, this method considers NaN equals to itself, and 0.0f unequal to -0.0f.)
Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
See Also:
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of floats are * <i>equal</i> to one another. Two arrays are considered equal if both * arrays contain the same number of elements, and all corresponding pairs * of elements in the two arrays are equal. In other words, two arrays * are equal if they contain the same elements in the same order. Also, * two array references are considered equal if both are <tt>null</tt>.<p> * * Two floats <tt>f1</tt> and <tt>f2</tt> are considered equal if: * <pre> <tt>new Float(f1).equals(new Float(f2))</tt></pre> * (Unlike the <tt>==</tt> operator, this method considers * <tt>NaN</tt> equals to itself, and 0.0f unequal to -0.0f.) * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal * @see Float#equals(Object) */
public static boolean equals(float[] a, float[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) if (Float.floatToIntBits(a[i])!=Float.floatToIntBits(a2[i])) return false; return true; }
Returns true if the two specified arrays of Objects are equal to one another. The two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. Two objects e1 and e2 are considered equal if (e1==null ? e2==null : e1.equals(e2)). In other words, the two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Params:
  • a – one array to be tested for equality
  • a2 – the other array to be tested for equality
Returns:true if the two arrays are equal
/** * Returns <tt>true</tt> if the two specified arrays of Objects are * <i>equal</i> to one another. The two arrays are considered equal if * both arrays contain the same number of elements, and all corresponding * pairs of elements in the two arrays are equal. Two objects <tt>e1</tt> * and <tt>e2</tt> are considered <i>equal</i> if <tt>(e1==null ? e2==null * : e1.equals(e2))</tt>. In other words, the two arrays are equal if * they contain the same elements in the same order. Also, two array * references are considered equal if both are <tt>null</tt>.<p> * * @param a one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal */
public static boolean equals(Object[] a, Object[] a2) { if (a==a2) return true; if (a==null || a2==null) return false; int length = a.length; if (a2.length != length) return false; for (int i=0; i<length; i++) { Object o1 = a[i]; Object o2 = a2[i]; if (!(o1==null ? o2==null : o1.equals(o2))) return false; } return true; } // Filling
Assigns the specified long value to each element of the specified array of longs.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified long value to each element of the specified array * of longs. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(long[] a, long val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified long value to each element of the specified range of the specified array of longs. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified long value to each element of the specified * range of the specified array of longs. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(long[] a, int fromIndex, int toIndex, long val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified int value to each element of the specified array of ints.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified int value to each element of the specified array * of ints. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(int[] a, int val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified int value to each element of the specified range of the specified array of ints. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified int value to each element of the specified * range of the specified array of ints. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(int[] a, int fromIndex, int toIndex, int val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified short value to each element of the specified array of shorts.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified short value to each element of the specified array * of shorts. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(short[] a, short val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified short value to each element of the specified range of the specified array of shorts. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified short value to each element of the specified * range of the specified array of shorts. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(short[] a, int fromIndex, int toIndex, short val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified char value to each element of the specified array of chars.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified char value to each element of the specified array * of chars. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(char[] a, char val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified char value to each element of the specified range of the specified array of chars. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified char value to each element of the specified * range of the specified array of chars. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(char[] a, int fromIndex, int toIndex, char val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified byte value to each element of the specified array of bytes.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified byte value to each element of the specified array * of bytes. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(byte[] a, byte val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified byte value to each element of the specified range of the specified array of bytes. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified byte value to each element of the specified * range of the specified array of bytes. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(byte[] a, int fromIndex, int toIndex, byte val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified boolean value to each element of the specified array of booleans.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified boolean value to each element of the specified * array of booleans. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(boolean[] a, boolean val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified boolean value to each element of the specified range of the specified array of booleans. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified boolean value to each element of the specified * range of the specified array of booleans. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(boolean[] a, int fromIndex, int toIndex, boolean val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified double value to each element of the specified array of doubles.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified double value to each element of the specified * array of doubles. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(double[] a, double val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified double value to each element of the specified range of the specified array of doubles. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified double value to each element of the specified * range of the specified array of doubles. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(double[] a, int fromIndex, int toIndex,double val){ rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified float value to each element of the specified array of floats.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
/** * Assigns the specified float value to each element of the specified array * of floats. * * @param a the array to be filled * @param val the value to be stored in all elements of the array */
public static void fill(float[] a, float val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified float value to each element of the specified range of the specified array of floats. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified float value to each element of the specified * range of the specified array of floats. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */
public static void fill(float[] a, int fromIndex, int toIndex, float val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; }
Assigns the specified Object reference to each element of the specified array of Objects.
Params:
  • a – the array to be filled
  • val – the value to be stored in all elements of the array
Throws:
  • ArrayStoreException – if the specified value is not of a runtime type that can be stored in the specified array
/** * Assigns the specified Object reference to each element of the specified * array of Objects. * * @param a the array to be filled * @param val the value to be stored in all elements of the array * @throws ArrayStoreException if the specified value is not of a * runtime type that can be stored in the specified array */
public static void fill(Object[] a, Object val) { for (int i = 0, len = a.length; i < len; i++) a[i] = val; }
Assigns the specified Object reference to each element of the specified range of the specified array of Objects. The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)
Params:
  • a – the array to be filled
  • fromIndex – the index of the first element (inclusive) to be filled with the specified value
  • toIndex – the index of the last element (exclusive) to be filled with the specified value
  • val – the value to be stored in all elements of the array
Throws:
/** * Assigns the specified Object reference to each element of the specified * range of the specified array of Objects. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> * @throws ArrayStoreException if the specified value is not of a * runtime type that can be stored in the specified array */
public static void fill(Object[] a, int fromIndex, int toIndex, Object val) { rangeCheck(a.length, fromIndex, toIndex); for (int i = fromIndex; i < toIndex; i++) a[i] = val; } // Cloning
Copies the specified array, truncating or padding with nulls (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain null. Such indices will exist if and only if the specified length is greater than that of the original array. The resulting array is of exactly the same class as the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Type parameters:
  • <T> – the class of the objects in the array
Throws:
Returns:a copy of the original array, truncated or padded with nulls to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with nulls (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>null</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * The resulting array is of exactly the same class as the original array. * * @param <T> the class of the objects in the array * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with nulls * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
@SuppressWarnings("unchecked") public static <T> T[] copyOf(T[] original, int newLength) { return (T[]) copyOf(original, newLength, original.getClass()); }
Copies the specified array, truncating or padding with nulls (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain null. Such indices will exist if and only if the specified length is greater than that of the original array. The resulting array is of the class newType.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
  • newType – the class of the copy to be returned
Type parameters:
  • <U> – the class of the objects in the original array
  • <T> – the class of the objects in the returned array
Throws:
Returns:a copy of the original array, truncated or padded with nulls to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with nulls (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>null</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * The resulting array is of the class <tt>newType</tt>. * * @param <U> the class of the objects in the original array * @param <T> the class of the objects in the returned array * @param original the array to be copied * @param newLength the length of the copy to be returned * @param newType the class of the copy to be returned * @return a copy of the original array, truncated or padded with nulls * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @throws ArrayStoreException if an element copied from * <tt>original</tt> is not of a runtime type that can be stored in * an array of class <tt>newType</tt> * @since 1.6 */
public static <T,U> T[] copyOf(U[] original, int newLength, Class<? extends T[]> newType) { @SuppressWarnings("unchecked") T[] copy = ((Object)newType == (Object)Object[].class) ? (T[]) new Object[newLength] : (T[]) Array.newInstance(newType.getComponentType(), newLength); System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain (byte)0. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with zeros to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with zeros (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>(byte)0</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with zeros * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static byte[] copyOf(byte[] original, int newLength) { byte[] copy = new byte[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain (short)0. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with zeros to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with zeros (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>(short)0</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with zeros * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static short[] copyOf(short[] original, int newLength) { short[] copy = new short[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with zeros to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with zeros (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>0</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with zeros * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static int[] copyOf(int[] original, int newLength) { int[] copy = new int[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0L. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with zeros to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with zeros (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>0L</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with zeros * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static long[] copyOf(long[] original, int newLength) { long[] copy = new long[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with null characters (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain '\\u000'. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with null characters to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with null characters (if necessary) * so the copy has the specified length. For all indices that are valid * in both the original array and the copy, the two arrays will contain * identical values. For any indices that are valid in the copy but not * the original, the copy will contain <tt>'\\u000'</tt>. Such indices * will exist if and only if the specified length is greater than that of * the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with null characters * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static char[] copyOf(char[] original, int newLength) { char[] copy = new char[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0f. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with zeros to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with zeros (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>0f</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with zeros * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static float[] copyOf(float[] original, int newLength) { float[] copy = new float[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0d. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with zeros to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with zeros (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>0d</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with zeros * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static double[] copyOf(double[] original, int newLength) { double[] copy = new double[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified array, truncating or padding with false (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain false. Such indices will exist if and only if the specified length is greater than that of the original array.
Params:
  • original – the array to be copied
  • newLength – the length of the copy to be returned
Throws:
Returns:a copy of the original array, truncated or padded with false elements to obtain the specified length
Since:1.6
/** * Copies the specified array, truncating or padding with <tt>false</tt> (if necessary) * so the copy has the specified length. For all indices that are * valid in both the original array and the copy, the two arrays will * contain identical values. For any indices that are valid in the * copy but not the original, the copy will contain <tt>false</tt>. * Such indices will exist if and only if the specified length * is greater than that of the original array. * * @param original the array to be copied * @param newLength the length of the copy to be returned * @return a copy of the original array, truncated or padded with false elements * to obtain the specified length * @throws NegativeArraySizeException if <tt>newLength</tt> is negative * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static boolean[] copyOf(boolean[] original, int newLength) { boolean[] copy = new boolean[newLength]; System.arraycopy(original, 0, copy, 0, Math.min(original.length, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case null is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.

The resulting array is of exactly the same class as the original array.

Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Type parameters:
  • <T> – the class of the objects in the array
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with nulls to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>null</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * <p> * The resulting array is of exactly the same class as the original array. * * @param <T> the class of the objects in the array * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with nulls to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
@SuppressWarnings("unchecked") public static <T> T[] copyOfRange(T[] original, int from, int to) { return copyOfRange(original, from, to, (Class<? extends T[]>) original.getClass()); }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case null is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from. The resulting array is of the class newType.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
  • newType – the class of the copy to be returned
Type parameters:
  • <U> – the class of the objects in the original array
  • <T> – the class of the objects in the returned array
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with nulls to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>null</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * The resulting array is of the class <tt>newType</tt>. * * @param <U> the class of the objects in the original array * @param <T> the class of the objects in the returned array * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @param newType the class of the copy to be returned * @return a new array containing the specified range from the original array, * truncated or padded with nulls to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @throws ArrayStoreException if an element copied from * <tt>original</tt> is not of a runtime type that can be stored in * an array of class <tt>newType</tt>. * @since 1.6 */
public static <T,U> T[] copyOfRange(U[] original, int from, int to, Class<? extends T[]> newType) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); @SuppressWarnings("unchecked") T[] copy = ((Object)newType == (Object)Object[].class) ? (T[]) new Object[newLength] : (T[]) Array.newInstance(newType.getComponentType(), newLength); System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case (byte)0 is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with zeros to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>(byte)0</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with zeros to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static byte[] copyOfRange(byte[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); byte[] copy = new byte[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case (short)0 is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with zeros to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>(short)0</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with zeros to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static short[] copyOfRange(short[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); short[] copy = new short[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case 0 is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with zeros to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>0</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with zeros to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static int[] copyOfRange(int[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); int[] copy = new int[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case 0L is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with zeros to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>0L</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with zeros to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static long[] copyOfRange(long[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); long[] copy = new long[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case '\\u000' is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with null characters to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>'\\u000'</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with null characters to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static char[] copyOfRange(char[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); char[] copy = new char[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case 0f is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with zeros to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>0f</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with zeros to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static float[] copyOfRange(float[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); float[] copy = new float[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case 0d is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with zeros to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>0d</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with zeros to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static double[] copyOfRange(double[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); double[] copy = new double[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; }
Copies the specified range of the specified array into a new array. The initial index of the range (from) must lie between zero and original.length, inclusive. The value at original[from] is placed into the initial element of the copy (unless from == original.length or from == to). Values from subsequent elements in the original array are placed into subsequent elements in the copy. The final index of the range (to), which must be greater than or equal to from, may be greater than original.length, in which case false is placed in all elements of the copy whose index is greater than or equal to original.length - from. The length of the returned array will be to - from.
Params:
  • original – the array from which a range is to be copied
  • from – the initial index of the range to be copied, inclusive
  • to – the final index of the range to be copied, exclusive. (This index may lie outside the array.)
Throws:
Returns:a new array containing the specified range from the original array, truncated or padded with false elements to obtain the required length
Since:1.6
/** * Copies the specified range of the specified array into a new array. * The initial index of the range (<tt>from</tt>) must lie between zero * and <tt>original.length</tt>, inclusive. The value at * <tt>original[from]</tt> is placed into the initial element of the copy * (unless <tt>from == original.length</tt> or <tt>from == to</tt>). * Values from subsequent elements in the original array are placed into * subsequent elements in the copy. The final index of the range * (<tt>to</tt>), which must be greater than or equal to <tt>from</tt>, * may be greater than <tt>original.length</tt>, in which case * <tt>false</tt> is placed in all elements of the copy whose index is * greater than or equal to <tt>original.length - from</tt>. The length * of the returned array will be <tt>to - from</tt>. * * @param original the array from which a range is to be copied * @param from the initial index of the range to be copied, inclusive * @param to the final index of the range to be copied, exclusive. * (This index may lie outside the array.) * @return a new array containing the specified range from the original array, * truncated or padded with false elements to obtain the required length * @throws ArrayIndexOutOfBoundsException if {@code from < 0} * or {@code from > original.length} * @throws IllegalArgumentException if <tt>from &gt; to</tt> * @throws NullPointerException if <tt>original</tt> is null * @since 1.6 */
public static boolean[] copyOfRange(boolean[] original, int from, int to) { int newLength = to - from; if (newLength < 0) throw new IllegalArgumentException(from + " > " + to); boolean[] copy = new boolean[newLength]; System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength)); return copy; } // Misc
Returns a fixed-size list backed by the specified array. (Changes to the returned list "write through" to the array.) This method acts as bridge between array-based and collection-based APIs, in combination with Collection.toArray. The returned list is serializable and implements RandomAccess.

This method also provides a convenient way to create a fixed-size list initialized to contain several elements:

    List<String> stooges = Arrays.asList("Larry", "Moe", "Curly");
Params:
  • a – the array by which the list will be backed
Type parameters:
  • <T> – the class of the objects in the array
Returns:a list view of the specified array
/** * Returns a fixed-size list backed by the specified array. (Changes to * the returned list "write through" to the array.) This method acts * as bridge between array-based and collection-based APIs, in * combination with {@link Collection#toArray}. The returned list is * serializable and implements {@link RandomAccess}. * * <p>This method also provides a convenient way to create a fixed-size * list initialized to contain several elements: * <pre> * List&lt;String&gt; stooges = Arrays.asList("Larry", "Moe", "Curly"); * </pre> * * @param <T> the class of the objects in the array * @param a the array by which the list will be backed * @return a list view of the specified array */
@SafeVarargs @SuppressWarnings("varargs") public static <T> List<T> asList(T... a) { return new ArrayList<>(a); }
@serialinclude
/** * @serial include */
private static class ArrayList<E> extends AbstractList<E> implements RandomAccess, java.io.Serializable { private static final long serialVersionUID = -2764017481108945198L; private final E[] a; ArrayList(E[] array) { a = Objects.requireNonNull(array); } @Override public int size() { return a.length; } @Override public Object[] toArray() { return a.clone(); } @Override @SuppressWarnings("unchecked") public <T> T[] toArray(T[] a) { int size = size(); if (a.length < size) return Arrays.copyOf(this.a, size, (Class<? extends T[]>) a.getClass()); System.arraycopy(this.a, 0, a, 0, size); if (a.length > size) a[size] = null; return a; } @Override public E get(int index) { return a[index]; } @Override public E set(int index, E element) { E oldValue = a[index]; a[index] = element; return oldValue; } @Override public int indexOf(Object o) { E[] a = this.a; if (o == null) { for (int i = 0; i < a.length; i++) if (a[i] == null) return i; } else { for (int i = 0; i < a.length; i++) if (o.equals(a[i])) return i; } return -1; } @Override public boolean contains(Object o) { return indexOf(o) != -1; } @Override public Spliterator<E> spliterator() { return Spliterators.spliterator(a, Spliterator.ORDERED); } @Override public void forEach(Consumer<? super E> action) { Objects.requireNonNull(action); for (E e : a) { action.accept(e); } } @Override public void replaceAll(UnaryOperator<E> operator) { Objects.requireNonNull(operator); E[] a = this.a; for (int i = 0; i < a.length; i++) { a[i] = operator.apply(a[i]); } } @Override public void sort(Comparator<? super E> c) { Arrays.sort(a, c); } }
Returns a hash code based on the contents of the specified array. For any two long arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Long instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two <tt>long</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Long} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(long a[]) { if (a == null) return 0; int result = 1; for (long element : a) { int elementHash = (int)(element ^ (element >>> 32)); result = 31 * result + elementHash; } return result; }
Returns a hash code based on the contents of the specified array. For any two non-null int arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Integer instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two non-null <tt>int</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Integer} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(int a[]) { if (a == null) return 0; int result = 1; for (int element : a) result = 31 * result + element; return result; }
Returns a hash code based on the contents of the specified array. For any two short arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Short instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two <tt>short</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Short} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(short a[]) { if (a == null) return 0; int result = 1; for (short element : a) result = 31 * result + element; return result; }
Returns a hash code based on the contents of the specified array. For any two char arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Character instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two <tt>char</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Character} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(char a[]) { if (a == null) return 0; int result = 1; for (char element : a) result = 31 * result + element; return result; }
Returns a hash code based on the contents of the specified array. For any two byte arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Byte instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two <tt>byte</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Byte} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(byte a[]) { if (a == null) return 0; int result = 1; for (byte element : a) result = 31 * result + element; return result; }
Returns a hash code based on the contents of the specified array. For any two boolean arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Boolean instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two <tt>boolean</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Boolean} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(boolean a[]) { if (a == null) return 0; int result = 1; for (boolean element : a) result = 31 * result + (element ? 1231 : 1237); return result; }
Returns a hash code based on the contents of the specified array. For any two float arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Float instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two <tt>float</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Float} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(float a[]) { if (a == null) return 0; int result = 1; for (float element : a) result = 31 * result + Float.floatToIntBits(element); return result; }
Returns a hash code based on the contents of the specified array. For any two double arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is the same value that would be obtained by invoking the hashCode method on a List containing a sequence of Double instances representing the elements of a in the same order. If a is null, this method returns 0.

Params:
  • a – the array whose hash value to compute
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. * For any two <tt>double</tt> arrays <tt>a</tt> and <tt>b</tt> * such that <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is the same value that would be * obtained by invoking the {@link List#hashCode() <tt>hashCode</tt>} * method on a {@link List} containing a sequence of {@link Double} * instances representing the elements of <tt>a</tt> in the same order. * If <tt>a</tt> is <tt>null</tt>, this method returns 0. * * @param a the array whose hash value to compute * @return a content-based hash code for <tt>a</tt> * @since 1.5 */
public static int hashCode(double a[]) { if (a == null) return 0; int result = 1; for (double element : a) { long bits = Double.doubleToLongBits(element); result = 31 * result + (int)(bits ^ (bits >>> 32)); } return result; }
Returns a hash code based on the contents of the specified array. If the array contains other arrays as elements, the hash code is based on their identities rather than their contents. It is therefore acceptable to invoke this method on an array that contains itself as an element, either directly or indirectly through one or more levels of arrays.

For any two arrays a and b such that Arrays.equals(a, b), it is also the case that Arrays.hashCode(a) == Arrays.hashCode(b).

The value returned by this method is equal to the value that would be returned by Arrays.asList(a).hashCode(), unless a is null, in which case 0 is returned.

Params:
  • a – the array whose content-based hash code to compute
See Also:
Returns:a content-based hash code for a
Since:1.5
/** * Returns a hash code based on the contents of the specified array. If * the array contains other arrays as elements, the hash code is based on * their identities rather than their contents. It is therefore * acceptable to invoke this method on an array that contains itself as an * element, either directly or indirectly through one or more levels of * arrays. * * <p>For any two arrays <tt>a</tt> and <tt>b</tt> such that * <tt>Arrays.equals(a, b)</tt>, it is also the case that * <tt>Arrays.hashCode(a) == Arrays.hashCode(b)</tt>. * * <p>The value returned by this method is equal to the value that would * be returned by <tt>Arrays.asList(a).hashCode()</tt>, unless <tt>a</tt> * is <tt>null</tt>, in which case <tt>0</tt> is returned. * * @param a the array whose content-based hash code to compute * @return a content-based hash code for <tt>a</tt> * @see #deepHashCode(Object[]) * @since 1.5 */
public static int hashCode(Object a[]) { if (a == null) return 0; int result = 1; for (Object element : a) result = 31 * result + (element == null ? 0 : element.hashCode()); return result; }
Returns a hash code based on the "deep contents" of the specified array. If the array contains other arrays as elements, the hash code is based on their contents and so on, ad infinitum. It is therefore unacceptable to invoke this method on an array that contains itself as an element, either directly or indirectly through one or more levels of arrays. The behavior of such an invocation is undefined.

For any two arrays a and b such that Arrays.deepEquals(a, b), it is also the case that Arrays.deepHashCode(a) == Arrays.deepHashCode(b).

The computation of the value returned by this method is similar to that of the value returned by List.hashCode() on a list containing the same elements as a in the same order, with one difference: If an element e of a is itself an array, its hash code is computed not by calling e.hashCode(), but as by calling the appropriate overloading of Arrays.hashCode(e) if e is an array of a primitive type, or as by calling Arrays.deepHashCode(e) recursively if e is an array of a reference type. If a is null, this method returns 0.

Params:
  • a – the array whose deep-content-based hash code to compute
See Also:
Returns:a deep-content-based hash code for a
Since:1.5
/** * Returns a hash code based on the "deep contents" of the specified * array. If the array contains other arrays as elements, the * hash code is based on their contents and so on, ad infinitum. * It is therefore unacceptable to invoke this method on an array that * contains itself as an element, either directly or indirectly through * one or more levels of arrays. The behavior of such an invocation is * undefined. * * <p>For any two arrays <tt>a</tt> and <tt>b</tt> such that * <tt>Arrays.deepEquals(a, b)</tt>, it is also the case that * <tt>Arrays.deepHashCode(a) == Arrays.deepHashCode(b)</tt>. * * <p>The computation of the value returned by this method is similar to * that of the value returned by {@link List#hashCode()} on a list * containing the same elements as <tt>a</tt> in the same order, with one * difference: If an element <tt>e</tt> of <tt>a</tt> is itself an array, * its hash code is computed not by calling <tt>e.hashCode()</tt>, but as * by calling the appropriate overloading of <tt>Arrays.hashCode(e)</tt> * if <tt>e</tt> is an array of a primitive type, or as by calling * <tt>Arrays.deepHashCode(e)</tt> recursively if <tt>e</tt> is an array * of a reference type. If <tt>a</tt> is <tt>null</tt>, this method * returns 0. * * @param a the array whose deep-content-based hash code to compute * @return a deep-content-based hash code for <tt>a</tt> * @see #hashCode(Object[]) * @since 1.5 */
public static int deepHashCode(Object a[]) { if (a == null) return 0; int result = 1; for (Object element : a) { int elementHash = 0; if (element instanceof Object[]) elementHash = deepHashCode((Object[]) element); else if (element instanceof byte[]) elementHash = hashCode((byte[]) element); else if (element instanceof short[]) elementHash = hashCode((short[]) element); else if (element instanceof int[]) elementHash = hashCode((int[]) element); else if (element instanceof long[]) elementHash = hashCode((long[]) element); else if (element instanceof char[]) elementHash = hashCode((char[]) element); else if (element instanceof float[]) elementHash = hashCode((float[]) element); else if (element instanceof double[]) elementHash = hashCode((double[]) element); else if (element instanceof boolean[]) elementHash = hashCode((boolean[]) element); else if (element != null) elementHash = element.hashCode(); result = 31 * result + elementHash; } return result; }
Returns true if the two specified arrays are deeply equal to one another. Unlike the equals(Object[], Object[]) method, this method is appropriate for use with nested arrays of arbitrary depth.

Two array references are considered deeply equal if both are null, or if they refer to arrays that contain the same number of elements and all corresponding pairs of elements in the two arrays are deeply equal.

Two possibly null elements e1 and e2 are deeply equal if any of the following conditions hold:

  • e1 and e2 are both arrays of object reference types, and Arrays.deepEquals(e1, e2) would return true
  • e1 and e2 are arrays of the same primitive type, and the appropriate overloading of Arrays.equals(e1, e2) would return true.
  • e1 == e2
  • e1.equals(e2) would return true.
Note that this definition permits null elements at any depth.

If either of the specified arrays contain themselves as elements either directly or indirectly through one or more levels of arrays, the behavior of this method is undefined.

Params:
  • a1 – one array to be tested for equality
  • a2 – the other array to be tested for equality
See Also:
Returns:true if the two arrays are equal
Since:1.5
/** * Returns <tt>true</tt> if the two specified arrays are <i>deeply * equal</i> to one another. Unlike the {@link #equals(Object[],Object[])} * method, this method is appropriate for use with nested arrays of * arbitrary depth. * * <p>Two array references are considered deeply equal if both * are <tt>null</tt>, or if they refer to arrays that contain the same * number of elements and all corresponding pairs of elements in the two * arrays are deeply equal. * * <p>Two possibly <tt>null</tt> elements <tt>e1</tt> and <tt>e2</tt> are * deeply equal if any of the following conditions hold: * <ul> * <li> <tt>e1</tt> and <tt>e2</tt> are both arrays of object reference * types, and <tt>Arrays.deepEquals(e1, e2) would return true</tt> * <li> <tt>e1</tt> and <tt>e2</tt> are arrays of the same primitive * type, and the appropriate overloading of * <tt>Arrays.equals(e1, e2)</tt> would return true. * <li> <tt>e1 == e2</tt> * <li> <tt>e1.equals(e2)</tt> would return true. * </ul> * Note that this definition permits <tt>null</tt> elements at any depth. * * <p>If either of the specified arrays contain themselves as elements * either directly or indirectly through one or more levels of arrays, * the behavior of this method is undefined. * * @param a1 one array to be tested for equality * @param a2 the other array to be tested for equality * @return <tt>true</tt> if the two arrays are equal * @see #equals(Object[],Object[]) * @see Objects#deepEquals(Object, Object) * @since 1.5 */
public static boolean deepEquals(Object[] a1, Object[] a2) { if (a1 == a2) return true; if (a1 == null || a2==null) return false; int length = a1.length; if (a2.length != length) return false; for (int i = 0; i < length; i++) { Object e1 = a1[i]; Object e2 = a2[i]; if (e1 == e2) continue; if (e1 == null) return false; // Figure out whether the two elements are equal boolean eq = deepEquals0(e1, e2); if (!eq) return false; } return true; } static boolean deepEquals0(Object e1, Object e2) { assert e1 != null; boolean eq; if (e1 instanceof Object[] && e2 instanceof Object[]) eq = deepEquals ((Object[]) e1, (Object[]) e2); else if (e1 instanceof byte[] && e2 instanceof byte[]) eq = equals((byte[]) e1, (byte[]) e2); else if (e1 instanceof short[] && e2 instanceof short[]) eq = equals((short[]) e1, (short[]) e2); else if (e1 instanceof int[] && e2 instanceof int[]) eq = equals((int[]) e1, (int[]) e2); else if (e1 instanceof long[] && e2 instanceof long[]) eq = equals((long[]) e1, (long[]) e2); else if (e1 instanceof char[] && e2 instanceof char[]) eq = equals((char[]) e1, (char[]) e2); else if (e1 instanceof float[] && e2 instanceof float[]) eq = equals((float[]) e1, (float[]) e2); else if (e1 instanceof double[] && e2 instanceof double[]) eq = equals((double[]) e1, (double[]) e2); else if (e1 instanceof boolean[] && e2 instanceof boolean[]) eq = equals((boolean[]) e1, (boolean[]) e2); else eq = e1.equals(e2); return eq; }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(long). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements are * separated by the characters <tt>", "</tt> (a comma followed by a * space). Elements are converted to strings as by * <tt>String.valueOf(long)</tt>. Returns <tt>"null"</tt> if <tt>a</tt> * is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(long[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(int). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements are * separated by the characters <tt>", "</tt> (a comma followed by a * space). Elements are converted to strings as by * <tt>String.valueOf(int)</tt>. Returns <tt>"null"</tt> if <tt>a</tt> is * <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(int[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(short). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements are * separated by the characters <tt>", "</tt> (a comma followed by a * space). Elements are converted to strings as by * <tt>String.valueOf(short)</tt>. Returns <tt>"null"</tt> if <tt>a</tt> * is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(short[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(char). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements are * separated by the characters <tt>", "</tt> (a comma followed by a * space). Elements are converted to strings as by * <tt>String.valueOf(char)</tt>. Returns <tt>"null"</tt> if <tt>a</tt> * is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(char[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(byte). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements * are separated by the characters <tt>", "</tt> (a comma followed * by a space). Elements are converted to strings as by * <tt>String.valueOf(byte)</tt>. Returns <tt>"null"</tt> if * <tt>a</tt> is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(byte[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(boolean). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements are * separated by the characters <tt>", "</tt> (a comma followed by a * space). Elements are converted to strings as by * <tt>String.valueOf(boolean)</tt>. Returns <tt>"null"</tt> if * <tt>a</tt> is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(boolean[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(float). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements are * separated by the characters <tt>", "</tt> (a comma followed by a * space). Elements are converted to strings as by * <tt>String.valueOf(float)</tt>. Returns <tt>"null"</tt> if <tt>a</tt> * is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(float[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(double). Returns "null" if a is null.
Params:
  • a – the array whose string representation to return
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * The string representation consists of a list of the array's elements, * enclosed in square brackets (<tt>"[]"</tt>). Adjacent elements are * separated by the characters <tt>", "</tt> (a comma followed by a * space). Elements are converted to strings as by * <tt>String.valueOf(double)</tt>. Returns <tt>"null"</tt> if <tt>a</tt> * is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @since 1.5 */
public static String toString(double[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(a[i]); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the contents of the specified array. If the array contains other arrays as elements, they are converted to strings by the Object.toString method inherited from Object, which describes their identities rather than their contents.

The value returned by this method is equal to the value that would be returned by Arrays.asList(a).toString(), unless a is null, in which case "null" is returned.

Params:
  • a – the array whose string representation to return
See Also:
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the contents of the specified array. * If the array contains other arrays as elements, they are converted to * strings by the {@link Object#toString} method inherited from * <tt>Object</tt>, which describes their <i>identities</i> rather than * their contents. * * <p>The value returned by this method is equal to the value that would * be returned by <tt>Arrays.asList(a).toString()</tt>, unless <tt>a</tt> * is <tt>null</tt>, in which case <tt>"null"</tt> is returned. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @see #deepToString(Object[]) * @since 1.5 */
public static String toString(Object[] a) { if (a == null) return "null"; int iMax = a.length - 1; if (iMax == -1) return "[]"; StringBuilder b = new StringBuilder(); b.append('['); for (int i = 0; ; i++) { b.append(String.valueOf(a[i])); if (i == iMax) return b.append(']').toString(); b.append(", "); } }
Returns a string representation of the "deep contents" of the specified array. If the array contains other arrays as elements, the string representation contains their contents and so on. This method is designed for converting multidimensional arrays to strings.

The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(Object), unless they are themselves arrays.

If an element e is an array of a primitive type, it is converted to a string as by invoking the appropriate overloading of Arrays.toString(e). If an element e is an array of a reference type, it is converted to a string as by invoking this method recursively.

To avoid infinite recursion, if the specified array contains itself as an element, or contains an indirect reference to itself through one or more levels of arrays, the self-reference is converted to the string "[...]". For example, an array containing only a reference to itself would be rendered as "[[...]]".

This method returns "null" if the specified array is null.

Params:
  • a – the array whose string representation to return
See Also:
Returns:a string representation of a
Since:1.5
/** * Returns a string representation of the "deep contents" of the specified * array. If the array contains other arrays as elements, the string * representation contains their contents and so on. This method is * designed for converting multidimensional arrays to strings. * * <p>The string representation consists of a list of the array's * elements, enclosed in square brackets (<tt>"[]"</tt>). Adjacent * elements are separated by the characters <tt>", "</tt> (a comma * followed by a space). Elements are converted to strings as by * <tt>String.valueOf(Object)</tt>, unless they are themselves * arrays. * * <p>If an element <tt>e</tt> is an array of a primitive type, it is * converted to a string as by invoking the appropriate overloading of * <tt>Arrays.toString(e)</tt>. If an element <tt>e</tt> is an array of a * reference type, it is converted to a string as by invoking * this method recursively. * * <p>To avoid infinite recursion, if the specified array contains itself * as an element, or contains an indirect reference to itself through one * or more levels of arrays, the self-reference is converted to the string * <tt>"[...]"</tt>. For example, an array containing only a reference * to itself would be rendered as <tt>"[[...]]"</tt>. * * <p>This method returns <tt>"null"</tt> if the specified array * is <tt>null</tt>. * * @param a the array whose string representation to return * @return a string representation of <tt>a</tt> * @see #toString(Object[]) * @since 1.5 */
public static String deepToString(Object[] a) { if (a == null) return "null"; int bufLen = 20 * a.length; if (a.length != 0 && bufLen <= 0) bufLen = Integer.MAX_VALUE; StringBuilder buf = new StringBuilder(bufLen); deepToString(a, buf, new HashSet<Object[]>()); return buf.toString(); } private static void deepToString(Object[] a, StringBuilder buf, Set<Object[]> dejaVu) { if (a == null) { buf.append("null"); return; } int iMax = a.length - 1; if (iMax == -1) { buf.append("[]"); return; } dejaVu.add(a); buf.append('['); for (int i = 0; ; i++) { Object element = a[i]; if (element == null) { buf.append("null"); } else { Class<?> eClass = element.getClass(); if (eClass.isArray()) { if (eClass == byte[].class) buf.append(toString((byte[]) element)); else if (eClass == short[].class) buf.append(toString((short[]) element)); else if (eClass == int[].class) buf.append(toString((int[]) element)); else if (eClass == long[].class) buf.append(toString((long[]) element)); else if (eClass == char[].class) buf.append(toString((char[]) element)); else if (eClass == float[].class) buf.append(toString((float[]) element)); else if (eClass == double[].class) buf.append(toString((double[]) element)); else if (eClass == boolean[].class) buf.append(toString((boolean[]) element)); else { // element is an array of object references if (dejaVu.contains(element)) buf.append("[...]"); else deepToString((Object[])element, buf, dejaVu); } } else { // element is non-null and not an array buf.append(element.toString()); } } if (i == iMax) break; buf.append(", "); } buf.append(']'); dejaVu.remove(a); }
Set all elements of the specified array, using the provided generator function to compute each element.

If the generator function throws an exception, it is relayed to the caller and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Type parameters:
  • <T> – type of elements of the array
Throws:
Since:1.8
/** * Set all elements of the specified array, using the provided * generator function to compute each element. * * <p>If the generator function throws an exception, it is relayed to * the caller and the array is left in an indeterminate state. * * @param <T> type of elements of the array * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static <T> void setAll(T[] array, IntFunction<? extends T> generator) { Objects.requireNonNull(generator); for (int i = 0; i < array.length; i++) array[i] = generator.apply(i); }
Set all elements of the specified array, in parallel, using the provided generator function to compute each element.

If the generator function throws an exception, an unchecked exception is thrown from parallelSetAll and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Type parameters:
  • <T> – type of elements of the array
Throws:
Since:1.8
/** * Set all elements of the specified array, in parallel, using the * provided generator function to compute each element. * * <p>If the generator function throws an exception, an unchecked exception * is thrown from {@code parallelSetAll} and the array is left in an * indeterminate state. * * @param <T> type of elements of the array * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static <T> void parallelSetAll(T[] array, IntFunction<? extends T> generator) { Objects.requireNonNull(generator); IntStream.range(0, array.length).parallel().forEach(i -> { array[i] = generator.apply(i); }); }
Set all elements of the specified array, using the provided generator function to compute each element.

If the generator function throws an exception, it is relayed to the caller and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Throws:
Since:1.8
/** * Set all elements of the specified array, using the provided * generator function to compute each element. * * <p>If the generator function throws an exception, it is relayed to * the caller and the array is left in an indeterminate state. * * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static void setAll(int[] array, IntUnaryOperator generator) { Objects.requireNonNull(generator); for (int i = 0; i < array.length; i++) array[i] = generator.applyAsInt(i); }
Set all elements of the specified array, in parallel, using the provided generator function to compute each element.

If the generator function throws an exception, an unchecked exception is thrown from parallelSetAll and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Throws:
Since:1.8
/** * Set all elements of the specified array, in parallel, using the * provided generator function to compute each element. * * <p>If the generator function throws an exception, an unchecked exception * is thrown from {@code parallelSetAll} and the array is left in an * indeterminate state. * * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static void parallelSetAll(int[] array, IntUnaryOperator generator) { Objects.requireNonNull(generator); IntStream.range(0, array.length).parallel().forEach(i -> { array[i] = generator.applyAsInt(i); }); }
Set all elements of the specified array, using the provided generator function to compute each element.

If the generator function throws an exception, it is relayed to the caller and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Throws:
Since:1.8
/** * Set all elements of the specified array, using the provided * generator function to compute each element. * * <p>If the generator function throws an exception, it is relayed to * the caller and the array is left in an indeterminate state. * * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static void setAll(long[] array, IntToLongFunction generator) { Objects.requireNonNull(generator); for (int i = 0; i < array.length; i++) array[i] = generator.applyAsLong(i); }
Set all elements of the specified array, in parallel, using the provided generator function to compute each element.

If the generator function throws an exception, an unchecked exception is thrown from parallelSetAll and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Throws:
Since:1.8
/** * Set all elements of the specified array, in parallel, using the * provided generator function to compute each element. * * <p>If the generator function throws an exception, an unchecked exception * is thrown from {@code parallelSetAll} and the array is left in an * indeterminate state. * * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static void parallelSetAll(long[] array, IntToLongFunction generator) { Objects.requireNonNull(generator); IntStream.range(0, array.length).parallel().forEach(i -> { array[i] = generator.applyAsLong(i); }); }
Set all elements of the specified array, using the provided generator function to compute each element.

If the generator function throws an exception, it is relayed to the caller and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Throws:
Since:1.8
/** * Set all elements of the specified array, using the provided * generator function to compute each element. * * <p>If the generator function throws an exception, it is relayed to * the caller and the array is left in an indeterminate state. * * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static void setAll(double[] array, IntToDoubleFunction generator) { Objects.requireNonNull(generator); for (int i = 0; i < array.length; i++) array[i] = generator.applyAsDouble(i); }
Set all elements of the specified array, in parallel, using the provided generator function to compute each element.

If the generator function throws an exception, an unchecked exception is thrown from parallelSetAll and the array is left in an indeterminate state.

Params:
  • array – array to be initialized
  • generator – a function accepting an index and producing the desired value for that position
Throws:
Since:1.8
/** * Set all elements of the specified array, in parallel, using the * provided generator function to compute each element. * * <p>If the generator function throws an exception, an unchecked exception * is thrown from {@code parallelSetAll} and the array is left in an * indeterminate state. * * @param array array to be initialized * @param generator a function accepting an index and producing the desired * value for that position * @throws NullPointerException if the generator is null * @since 1.8 */
public static void parallelSetAll(double[] array, IntToDoubleFunction generator) { Objects.requireNonNull(generator); IntStream.range(0, array.length).parallel().forEach(i -> { array[i] = generator.applyAsDouble(i); }); }
Returns a Spliterator covering all of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
Type parameters:
  • <T> – type of elements
Returns:a spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator} covering all of the specified array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param <T> type of elements * @param array the array, assumed to be unmodified during use * @return a spliterator for the array elements * @since 1.8 */
public static <T> Spliterator<T> spliterator(T[] array) { return Spliterators.spliterator(array, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a Spliterator covering the specified range of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Type parameters:
  • <T> – type of elements
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:a spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator} covering the specified range of the * specified array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param <T> type of elements * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return a spliterator for the array elements * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static <T> Spliterator<T> spliterator(T[] array, int startInclusive, int endExclusive) { return Spliterators.spliterator(array, startInclusive, endExclusive, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a OfInt covering all of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
Returns:a spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator.OfInt} covering all of the specified array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param array the array, assumed to be unmodified during use * @return a spliterator for the array elements * @since 1.8 */
public static Spliterator.OfInt spliterator(int[] array) { return Spliterators.spliterator(array, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a OfInt covering the specified range of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:a spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator.OfInt} covering the specified range of the * specified array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return a spliterator for the array elements * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static Spliterator.OfInt spliterator(int[] array, int startInclusive, int endExclusive) { return Spliterators.spliterator(array, startInclusive, endExclusive, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a OfLong covering all of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
Returns:the spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator.OfLong} covering all of the specified array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param array the array, assumed to be unmodified during use * @return the spliterator for the array elements * @since 1.8 */
public static Spliterator.OfLong spliterator(long[] array) { return Spliterators.spliterator(array, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a OfLong covering the specified range of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:a spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator.OfLong} covering the specified range of the * specified array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return a spliterator for the array elements * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static Spliterator.OfLong spliterator(long[] array, int startInclusive, int endExclusive) { return Spliterators.spliterator(array, startInclusive, endExclusive, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a OfDouble covering all of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
Returns:a spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator.OfDouble} covering all of the specified * array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param array the array, assumed to be unmodified during use * @return a spliterator for the array elements * @since 1.8 */
public static Spliterator.OfDouble spliterator(double[] array) { return Spliterators.spliterator(array, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a OfDouble covering the specified range of the specified array.

The spliterator reports Spliterator.SIZED, Spliterator.SUBSIZED, Spliterator.ORDERED, and Spliterator.IMMUTABLE.

Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:a spliterator for the array elements
Since:1.8
/** * Returns a {@link Spliterator.OfDouble} covering the specified range of * the specified array. * * <p>The spliterator reports {@link Spliterator#SIZED}, * {@link Spliterator#SUBSIZED}, {@link Spliterator#ORDERED}, and * {@link Spliterator#IMMUTABLE}. * * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return a spliterator for the array elements * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static Spliterator.OfDouble spliterator(double[] array, int startInclusive, int endExclusive) { return Spliterators.spliterator(array, startInclusive, endExclusive, Spliterator.ORDERED | Spliterator.IMMUTABLE); }
Returns a sequential Stream with the specified array as its source.
Params:
  • array – The array, assumed to be unmodified during use
Type parameters:
  • <T> – The type of the array elements
Returns:a Stream for the array
Since:1.8
/** * Returns a sequential {@link Stream} with the specified array as its * source. * * @param <T> The type of the array elements * @param array The array, assumed to be unmodified during use * @return a {@code Stream} for the array * @since 1.8 */
public static <T> Stream<T> stream(T[] array) { return stream(array, 0, array.length); }
Returns a sequential Stream with the specified range of the specified array as its source.
Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Type parameters:
  • <T> – the type of the array elements
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:a Stream for the array range
Since:1.8
/** * Returns a sequential {@link Stream} with the specified range of the * specified array as its source. * * @param <T> the type of the array elements * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return a {@code Stream} for the array range * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static <T> Stream<T> stream(T[] array, int startInclusive, int endExclusive) { return StreamSupport.stream(spliterator(array, startInclusive, endExclusive), false); }
Returns a sequential IntStream with the specified array as its source.
Params:
  • array – the array, assumed to be unmodified during use
Returns:an IntStream for the array
Since:1.8
/** * Returns a sequential {@link IntStream} with the specified array as its * source. * * @param array the array, assumed to be unmodified during use * @return an {@code IntStream} for the array * @since 1.8 */
public static IntStream stream(int[] array) { return stream(array, 0, array.length); }
Returns a sequential IntStream with the specified range of the specified array as its source.
Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:an IntStream for the array range
Since:1.8
/** * Returns a sequential {@link IntStream} with the specified range of the * specified array as its source. * * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return an {@code IntStream} for the array range * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static IntStream stream(int[] array, int startInclusive, int endExclusive) { return StreamSupport.intStream(spliterator(array, startInclusive, endExclusive), false); }
Returns a sequential LongStream with the specified array as its source.
Params:
  • array – the array, assumed to be unmodified during use
Returns:a LongStream for the array
Since:1.8
/** * Returns a sequential {@link LongStream} with the specified array as its * source. * * @param array the array, assumed to be unmodified during use * @return a {@code LongStream} for the array * @since 1.8 */
public static LongStream stream(long[] array) { return stream(array, 0, array.length); }
Returns a sequential LongStream with the specified range of the specified array as its source.
Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:a LongStream for the array range
Since:1.8
/** * Returns a sequential {@link LongStream} with the specified range of the * specified array as its source. * * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return a {@code LongStream} for the array range * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static LongStream stream(long[] array, int startInclusive, int endExclusive) { return StreamSupport.longStream(spliterator(array, startInclusive, endExclusive), false); }
Returns a sequential DoubleStream with the specified array as its source.
Params:
  • array – the array, assumed to be unmodified during use
Returns:a DoubleStream for the array
Since:1.8
/** * Returns a sequential {@link DoubleStream} with the specified array as its * source. * * @param array the array, assumed to be unmodified during use * @return a {@code DoubleStream} for the array * @since 1.8 */
public static DoubleStream stream(double[] array) { return stream(array, 0, array.length); }
Returns a sequential DoubleStream with the specified range of the specified array as its source.
Params:
  • array – the array, assumed to be unmodified during use
  • startInclusive – the first index to cover, inclusive
  • endExclusive – index immediately past the last index to cover
Throws:
  • ArrayIndexOutOfBoundsException – if startInclusive is negative, endExclusive is less than startInclusive, or endExclusive is greater than the array size
Returns:a DoubleStream for the array range
Since:1.8
/** * Returns a sequential {@link DoubleStream} with the specified range of the * specified array as its source. * * @param array the array, assumed to be unmodified during use * @param startInclusive the first index to cover, inclusive * @param endExclusive index immediately past the last index to cover * @return a {@code DoubleStream} for the array range * @throws ArrayIndexOutOfBoundsException if {@code startInclusive} is * negative, {@code endExclusive} is less than * {@code startInclusive}, or {@code endExclusive} is greater than * the array size * @since 1.8 */
public static DoubleStream stream(double[] array, int startInclusive, int endExclusive) { return StreamSupport.doubleStream(spliterator(array, startInclusive, endExclusive), false); } }