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package java.lang;

import jdk.internal.math.FloatingDecimal;

import java.util.Arrays;
import java.util.Spliterator;
import java.util.stream.IntStream;
import java.util.stream.StreamSupport;
import jdk.internal.util.ArraysSupport;

import static java.lang.String.COMPACT_STRINGS;
import static java.lang.String.UTF16;
import static java.lang.String.LATIN1;
import static java.lang.String.checkIndex;
import static java.lang.String.checkOffset;

A mutable sequence of characters.

Implements a modifiable string. At any point in time it contains some particular sequence of characters, but the length and content of the sequence can be changed through certain method calls.

Unless otherwise noted, passing a null argument to a constructor or method in this class will cause a NullPointerException to be thrown.

Author: Michael McCloskey, Martin Buchholz, Ulf Zibis
Since: 1.5
/** * A mutable sequence of characters. * <p> * Implements a modifiable string. At any point in time it contains some * particular sequence of characters, but the length and content of the * sequence can be changed through certain method calls. * * <p>Unless otherwise noted, passing a {@code null} argument to a constructor * or method in this class will cause a {@link NullPointerException} to be * thrown. * * @author Michael McCloskey * @author Martin Buchholz * @author Ulf Zibis * @since 1.5 */
abstract class AbstractStringBuilder implements Appendable, CharSequence {
The value is used for character storage.
/** * The value is used for character storage. */
byte[] value;
The id of the encoding used to encode the bytes in value.
/** * The id of the encoding used to encode the bytes in {@code value}. */
byte coder;
The count is the number of characters used.
/** * The count is the number of characters used. */
int count; private static final byte[] EMPTYVALUE = new byte[0];
This no-arg constructor is necessary for serialization of subclasses.
/** * This no-arg constructor is necessary for serialization of subclasses. */
AbstractStringBuilder() { value = EMPTYVALUE; }
Creates an AbstractStringBuilder of the specified capacity.
/** * Creates an AbstractStringBuilder of the specified capacity. */
AbstractStringBuilder(int capacity) { if (COMPACT_STRINGS) { value = new byte[capacity]; coder = LATIN1; } else { value = StringUTF16.newBytesFor(capacity); coder = UTF16; } }
Constructs an AbstractStringBuilder that contains the same characters as the specified String. The initial capacity of the string builder is 16 plus the length of the String argument.
Params:
  • str – the string to copy.
/** * Constructs an AbstractStringBuilder that contains the same characters * as the specified {@code String}. The initial capacity of * the string builder is {@code 16} plus the length of the * {@code String} argument. * * @param str the string to copy. */
AbstractStringBuilder(String str) { int length = str.length(); int capacity = (length < Integer.MAX_VALUE - 16) ? length + 16 : Integer.MAX_VALUE; final byte initCoder = str.coder(); coder = initCoder; value = (initCoder == LATIN1) ? new byte[capacity] : StringUTF16.newBytesFor(capacity); append(str); }
Constructs an AbstractStringBuilder that contains the same characters as the specified CharSequence. The initial capacity of the string builder is 16 plus the length of the CharSequence argument.
Params:
  • seq – the sequence to copy.
/** * Constructs an AbstractStringBuilder that contains the same characters * as the specified {@code CharSequence}. The initial capacity of * the string builder is {@code 16} plus the length of the * {@code CharSequence} argument. * * @param seq the sequence to copy. */
AbstractStringBuilder(CharSequence seq) { int length = seq.length(); if (length < 0) { throw new NegativeArraySizeException("Negative length: " + length); } int capacity = (length < Integer.MAX_VALUE - 16) ? length + 16 : Integer.MAX_VALUE; final byte initCoder; if (COMPACT_STRINGS) { if (seq instanceof AbstractStringBuilder) { initCoder = ((AbstractStringBuilder)seq).getCoder(); } else if (seq instanceof String) { initCoder = ((String)seq).coder(); } else { initCoder = LATIN1; } } else { initCoder = UTF16; } coder = initCoder; value = (initCoder == LATIN1) ? new byte[capacity] : StringUTF16.newBytesFor(capacity); append(seq); }
Compares the objects of two AbstractStringBuilder implementations lexicographically.
Since:11
/** * Compares the objects of two AbstractStringBuilder implementations lexicographically. * * @since 11 */
int compareTo(AbstractStringBuilder another) { if (this == another) { return 0; } byte[] val1 = value; byte[] val2 = another.value; int count1 = this.count; int count2 = another.count; if (coder == another.coder) { return isLatin1() ? StringLatin1.compareTo(val1, val2, count1, count2) : StringUTF16.compareTo(val1, val2, count1, count2); } return isLatin1() ? StringLatin1.compareToUTF16(val1, val2, count1, count2) : StringUTF16.compareToLatin1(val1, val2, count1, count2); }
Returns the length (character count).
Returns: the length of the sequence of characters currently represented by this object
/** * Returns the length (character count). * * @return the length of the sequence of characters currently * represented by this object */
@Override public int length() { return count; }
Returns the current capacity. The capacity is the number of characters that can be stored (including already written characters), beyond which an allocation will occur.
Returns: the current capacity
/** * Returns the current capacity. The capacity is the number of characters * that can be stored (including already written characters), beyond which * an allocation will occur. * * @return the current capacity */
public int capacity() { return value.length >> coder; }
Ensures that the capacity is at least equal to the specified minimum. If the current capacity is less than the argument, then a new internal array is allocated with greater capacity. The new capacity is the larger of:
  • The minimumCapacity argument.
  • Twice the old capacity, plus 2.
If the minimumCapacity argument is nonpositive, this method takes no action and simply returns. Note that subsequent operations on this object can reduce the actual capacity below that requested here.
Params:
  • minimumCapacity – the minimum desired capacity.
/** * Ensures that the capacity is at least equal to the specified minimum. * If the current capacity is less than the argument, then a new internal * array is allocated with greater capacity. The new capacity is the * larger of: * <ul> * <li>The {@code minimumCapacity} argument. * <li>Twice the old capacity, plus {@code 2}. * </ul> * If the {@code minimumCapacity} argument is nonpositive, this * method takes no action and simply returns. * Note that subsequent operations on this object can reduce the * actual capacity below that requested here. * * @param minimumCapacity the minimum desired capacity. */
public void ensureCapacity(int minimumCapacity) { if (minimumCapacity > 0) { ensureCapacityInternal(minimumCapacity); } }
For positive values of minimumCapacity, this method behaves like ensureCapacity, however it is never synchronized. If minimumCapacity is non positive due to numeric overflow, this method throws OutOfMemoryError.
/** * For positive values of {@code minimumCapacity}, this method * behaves like {@code ensureCapacity}, however it is never * synchronized. * If {@code minimumCapacity} is non positive due to numeric * overflow, this method throws {@code OutOfMemoryError}. */
private void ensureCapacityInternal(int minimumCapacity) { // overflow-conscious code int oldCapacity = value.length >> coder; if (minimumCapacity - oldCapacity > 0) { value = Arrays.copyOf(value, newCapacity(minimumCapacity) << coder); } }
The maximum size of array to allocate (unless necessary). Some VMs reserve some header words in an array. Attempts to allocate larger arrays may result in OutOfMemoryError: Requested array size exceeds VM limit
/** * The maximum size of array to allocate (unless necessary). * Some VMs reserve some header words in an array. * Attempts to allocate larger arrays may result in * OutOfMemoryError: Requested array size exceeds VM limit */
private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
Returns a capacity at least as large as the given minimum capacity. Returns the current capacity increased by the current length + 2 if that suffices. Will not return a capacity greater than (MAX_ARRAY_SIZE >> coder) unless the given minimum capacity is greater than that.
Params:
  • minCapacity – the desired minimum capacity
Throws:
  • OutOfMemoryError – if minCapacity is less than zero or greater than (Integer.MAX_VALUE >> coder)
/** * Returns a capacity at least as large as the given minimum capacity. * Returns the current capacity increased by the current length + 2 if * that suffices. * Will not return a capacity greater than * {@code (MAX_ARRAY_SIZE >> coder)} unless the given minimum capacity * is greater than that. * * @param minCapacity the desired minimum capacity * @throws OutOfMemoryError if minCapacity is less than zero or * greater than (Integer.MAX_VALUE >> coder) */
private int newCapacity(int minCapacity) { int oldLength = value.length; int newLength = minCapacity << coder; int growth = newLength - oldLength; int length = ArraysSupport.newLength(oldLength, growth, oldLength + (2 << coder)); if (length == Integer.MAX_VALUE) { throw new OutOfMemoryError("Required length exceeds implementation limit"); } return length >> coder; }
If the coder is "isLatin1", this inflates the internal 8-bit storage to 16-bit pair storage.
/** * If the coder is "isLatin1", this inflates the internal 8-bit storage * to 16-bit <hi=0, low> pair storage. */
private void inflate() { if (!isLatin1()) { return; } byte[] buf = StringUTF16.newBytesFor(value.length); StringLatin1.inflate(value, 0, buf, 0, count); this.value = buf; this.coder = UTF16; }
Attempts to reduce storage used for the character sequence. If the buffer is larger than necessary to hold its current sequence of characters, then it may be resized to become more space efficient. Calling this method may, but is not required to, affect the value returned by a subsequent call to the capacity() method.
/** * Attempts to reduce storage used for the character sequence. * If the buffer is larger than necessary to hold its current sequence of * characters, then it may be resized to become more space efficient. * Calling this method may, but is not required to, affect the value * returned by a subsequent call to the {@link #capacity()} method. */
public void trimToSize() { int length = count << coder; if (length < value.length) { value = Arrays.copyOf(value, length); } }
Sets the length of the character sequence. The sequence is changed to a new character sequence whose length is specified by the argument. For every nonnegative index k less than newLength, the character at index k in the new character sequence is the same as the character at index k in the old sequence if k is less than the length of the old character sequence; otherwise, it is the null character '\u005Cu0000'. In other words, if the newLength argument is less than the current length, the length is changed to the specified length.

If the newLength argument is greater than or equal to the current length, sufficient null characters ('\u005Cu0000') are appended so that length becomes the newLength argument.

The newLength argument must be greater than or equal to 0.

Params:
  • newLength – the new length
Throws:
/** * Sets the length of the character sequence. * The sequence is changed to a new character sequence * whose length is specified by the argument. For every nonnegative * index <i>k</i> less than {@code newLength}, the character at * index <i>k</i> in the new character sequence is the same as the * character at index <i>k</i> in the old sequence if <i>k</i> is less * than the length of the old character sequence; otherwise, it is the * null character {@code '\u005Cu0000'}. * * In other words, if the {@code newLength} argument is less than * the current length, the length is changed to the specified length. * <p> * If the {@code newLength} argument is greater than or equal * to the current length, sufficient null characters * ({@code '\u005Cu0000'}) are appended so that * length becomes the {@code newLength} argument. * <p> * The {@code newLength} argument must be greater than or equal * to {@code 0}. * * @param newLength the new length * @throws IndexOutOfBoundsException if the * {@code newLength} argument is negative. */
public void setLength(int newLength) { if (newLength < 0) { throw new StringIndexOutOfBoundsException(newLength); } ensureCapacityInternal(newLength); if (count < newLength) { if (isLatin1()) { StringLatin1.fillNull(value, count, newLength); } else { StringUTF16.fillNull(value, count, newLength); } } count = newLength; }
Returns the char value in this sequence at the specified index. The first char value is at index 0, the next at index 1, and so on, as in array indexing.

The index argument must be greater than or equal to 0, and less than the length of this sequence.

If the char value specified by the index is a surrogate, the surrogate value is returned.

Params:
  • index – the index of the desired char value.
Throws:
Returns: the char value at the specified index.
/** * Returns the {@code char} value in this sequence at the specified index. * The first {@code char} value is at index {@code 0}, the next at index * {@code 1}, and so on, as in array indexing. * <p> * The index argument must be greater than or equal to * {@code 0}, and less than the length of this sequence. * * <p>If the {@code char} value specified by the index is a * <a href="Character.html#unicode">surrogate</a>, the surrogate * value is returned. * * @param index the index of the desired {@code char} value. * @return the {@code char} value at the specified index. * @throws IndexOutOfBoundsException if {@code index} is * negative or greater than or equal to {@code length()}. */
@Override public char charAt(int index) { checkIndex(index, count); if (isLatin1()) { return (char)(value[index] & 0xff); } return StringUTF16.charAt(value, index); }
Returns the character (Unicode code point) at the specified index. The index refers to char values (Unicode code units) and ranges from 0 to length() - 1.

If the char value specified at the given index is in the high-surrogate range, the following index is less than the length of this sequence, and the char value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char value at the given index is returned.

Params:
  • index – the index to the char values
Throws:
Returns: the code point value of the character at the index
/** * Returns the character (Unicode code point) at the specified * index. The index refers to {@code char} values * (Unicode code units) and ranges from {@code 0} to * {@link #length()}{@code - 1}. * * <p> If the {@code char} value specified at the given index * is in the high-surrogate range, the following index is less * than the length of this sequence, and the * {@code char} value at the following index is in the * low-surrogate range, then the supplementary code point * corresponding to this surrogate pair is returned. Otherwise, * the {@code char} value at the given index is returned. * * @param index the index to the {@code char} values * @return the code point value of the character at the * {@code index} * @throws IndexOutOfBoundsException if the {@code index} * argument is negative or not less than the length of this * sequence. */
public int codePointAt(int index) { int count = this.count; byte[] value = this.value; checkIndex(index, count); if (isLatin1()) { return value[index] & 0xff; } return StringUTF16.codePointAtSB(value, index, count); }
Returns the character (Unicode code point) before the specified index. The index refers to char values (Unicode code units) and ranges from 1 to length().

If the char value at (index - 1) is in the low-surrogate range, (index - 2) is not negative, and the char value at (index - 2) is in the high-surrogate range, then the supplementary code point value of the surrogate pair is returned. If the char value at index - 1 is an unpaired low-surrogate or a high-surrogate, the surrogate value is returned.

Params:
  • index – the index following the code point that should be returned
Throws:
Returns: the Unicode code point value before the given index.
/** * Returns the character (Unicode code point) before the specified * index. The index refers to {@code char} values * (Unicode code units) and ranges from {@code 1} to {@link * #length()}. * * <p> If the {@code char} value at {@code (index - 1)} * is in the low-surrogate range, {@code (index - 2)} is not * negative, and the {@code char} value at {@code (index - * 2)} is in the high-surrogate range, then the * supplementary code point value of the surrogate pair is * returned. If the {@code char} value at {@code index - * 1} is an unpaired low-surrogate or a high-surrogate, the * surrogate value is returned. * * @param index the index following the code point that should be returned * @return the Unicode code point value before the given index. * @throws IndexOutOfBoundsException if the {@code index} * argument is less than 1 or greater than the length * of this sequence. */
public int codePointBefore(int index) { int i = index - 1; if (i < 0 || i >= count) { throw new StringIndexOutOfBoundsException(index); } if (isLatin1()) { return value[i] & 0xff; } return StringUTF16.codePointBeforeSB(value, index); }
Returns the number of Unicode code points in the specified text range of this sequence. The text range begins at the specified beginIndex and extends to the char at index endIndex - 1. Thus the length (in chars) of the text range is endIndex-beginIndex. Unpaired surrogates within this sequence count as one code point each.
Params:
  • beginIndex – the index to the first char of the text range.
  • endIndex – the index after the last char of the text range.
Throws:
  • IndexOutOfBoundsException – if the beginIndex is negative, or endIndex is larger than the length of this sequence, or beginIndex is larger than endIndex.
Returns:the number of Unicode code points in the specified text range
/** * Returns the number of Unicode code points in the specified text * range of this sequence. The text range begins at the specified * {@code beginIndex} and extends to the {@code char} at * index {@code endIndex - 1}. Thus the length (in * {@code char}s) of the text range is * {@code endIndex-beginIndex}. Unpaired surrogates within * this sequence count as one code point each. * * @param beginIndex the index to the first {@code char} of * the text range. * @param endIndex the index after the last {@code char} of * the text range. * @return the number of Unicode code points in the specified text * range * @throws IndexOutOfBoundsException if the * {@code beginIndex} is negative, or {@code endIndex} * is larger than the length of this sequence, or * {@code beginIndex} is larger than {@code endIndex}. */
public int codePointCount(int beginIndex, int endIndex) { if (beginIndex < 0 || endIndex > count || beginIndex > endIndex) { throw new IndexOutOfBoundsException(); } if (isLatin1()) { return endIndex - beginIndex; } return StringUTF16.codePointCountSB(value, beginIndex, endIndex); }
Returns the index within this sequence that is offset from the given index by codePointOffset code points. Unpaired surrogates within the text range given by index and codePointOffset count as one code point each.
Params:
  • index – the index to be offset
  • codePointOffset – the offset in code points
Throws:
  • IndexOutOfBoundsException – if index is negative or larger then the length of this sequence, or if codePointOffset is positive and the subsequence starting with index has fewer than codePointOffset code points, or if codePointOffset is negative and the subsequence before index has fewer than the absolute value of codePointOffset code points.
Returns:the index within this sequence
/** * Returns the index within this sequence that is offset from the * given {@code index} by {@code codePointOffset} code * points. Unpaired surrogates within the text range given by * {@code index} and {@code codePointOffset} count as * one code point each. * * @param index the index to be offset * @param codePointOffset the offset in code points * @return the index within this sequence * @throws IndexOutOfBoundsException if {@code index} * is negative or larger then the length of this sequence, * or if {@code codePointOffset} is positive and the subsequence * starting with {@code index} has fewer than * {@code codePointOffset} code points, * or if {@code codePointOffset} is negative and the subsequence * before {@code index} has fewer than the absolute value of * {@code codePointOffset} code points. */
public int offsetByCodePoints(int index, int codePointOffset) { if (index < 0 || index > count) { throw new IndexOutOfBoundsException(); } return Character.offsetByCodePoints(this, index, codePointOffset); }
Characters are copied from this sequence into the destination character array dst. The first character to be copied is at index srcBegin; the last character to be copied is at index srcEnd-1. The total number of characters to be copied is srcEnd-srcBegin. The characters are copied into the subarray of dst starting at index dstBegin and ending at index:

dstbegin + (srcEnd-srcBegin) - 1
Params:
  • srcBegin – start copying at this offset.
  • srcEnd – stop copying at this offset.
  • dst – the array to copy the data into.
  • dstBegin – offset into dst.
Throws:
  • IndexOutOfBoundsException – if any of the following is true:
    • srcBegin is negative
    • dstBegin is negative
    • the srcBegin argument is greater than the srcEnd argument.
    • srcEnd is greater than this.length().
    • dstBegin+srcEnd-srcBegin is greater than dst.length
/** * Characters are copied from this sequence into the * destination character array {@code dst}. The first character to * be copied is at index {@code srcBegin}; the last character to * be copied is at index {@code srcEnd-1}. The total number of * characters to be copied is {@code srcEnd-srcBegin}. The * characters are copied into the subarray of {@code dst} starting * at index {@code dstBegin} and ending at index: * <pre>{@code * dstbegin + (srcEnd-srcBegin) - 1 * }</pre> * * @param srcBegin start copying at this offset. * @param srcEnd stop copying at this offset. * @param dst the array to copy the data into. * @param dstBegin offset into {@code dst}. * @throws IndexOutOfBoundsException if any of the following is true: * <ul> * <li>{@code srcBegin} is negative * <li>{@code dstBegin} is negative * <li>the {@code srcBegin} argument is greater than * the {@code srcEnd} argument. * <li>{@code srcEnd} is greater than * {@code this.length()}. * <li>{@code dstBegin+srcEnd-srcBegin} is greater than * {@code dst.length} * </ul> */
public void getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin) { checkRangeSIOOBE(srcBegin, srcEnd, count); // compatible to old version int n = srcEnd - srcBegin; checkRange(dstBegin, dstBegin + n, dst.length); if (isLatin1()) { StringLatin1.getChars(value, srcBegin, srcEnd, dst, dstBegin); } else { StringUTF16.getChars(value, srcBegin, srcEnd, dst, dstBegin); } }
The character at the specified index is set to ch. This sequence is altered to represent a new character sequence that is identical to the old character sequence, except that it contains the character ch at position index.

The index argument must be greater than or equal to 0, and less than the length of this sequence.

Params:
  • index – the index of the character to modify.
  • ch – the new character.
Throws:
/** * The character at the specified index is set to {@code ch}. This * sequence is altered to represent a new character sequence that is * identical to the old character sequence, except that it contains the * character {@code ch} at position {@code index}. * <p> * The index argument must be greater than or equal to * {@code 0}, and less than the length of this sequence. * * @param index the index of the character to modify. * @param ch the new character. * @throws IndexOutOfBoundsException if {@code index} is * negative or greater than or equal to {@code length()}. */
public void setCharAt(int index, char ch) { checkIndex(index, count); if (isLatin1() && StringLatin1.canEncode(ch)) { value[index] = (byte)ch; } else { if (isLatin1()) { inflate(); } StringUTF16.putCharSB(value, index, ch); } }
Appends the string representation of the Object argument.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(Object), and the characters of that string were then appended to this character sequence.

Params:
  • obj – an Object.
Returns: a reference to this object.
/** * Appends the string representation of the {@code Object} argument. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(Object)}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param obj an {@code Object}. * @return a reference to this object. */
public AbstractStringBuilder append(Object obj) { return append(String.valueOf(obj)); }
Appends the specified string to this character sequence.

The characters of the String argument are appended, in order, increasing the length of this sequence by the length of the argument. If str is null, then the four characters "null" are appended.

Let n be the length of this character sequence just prior to execution of the append method. Then the character at index k in the new character sequence is equal to the character at index k in the old character sequence, if k is less than n; otherwise, it is equal to the character at index k-n in the argument str.

Params:
  • str – a string.
Returns: a reference to this object.
/** * Appends the specified string to this character sequence. * <p> * The characters of the {@code String} argument are appended, in * order, increasing the length of this sequence by the length of the * argument. If {@code str} is {@code null}, then the four * characters {@code "null"} are appended. * <p> * Let <i>n</i> be the length of this character sequence just prior to * execution of the {@code append} method. Then the character at * index <i>k</i> in the new character sequence is equal to the character * at index <i>k</i> in the old character sequence, if <i>k</i> is less * than <i>n</i>; otherwise, it is equal to the character at index * <i>k-n</i> in the argument {@code str}. * * @param str a string. * @return a reference to this object. */
public AbstractStringBuilder append(String str) { if (str == null) { return appendNull(); } int len = str.length(); ensureCapacityInternal(count + len); putStringAt(count, str); count += len; return this; }
Appends the specified StringBuffer to this sequence.
Params:
  • sb – the StringBuffer to append.
Returns: a reference to this object.
/** * Appends the specified {@code StringBuffer} to this sequence. * * @param sb the {@code StringBuffer} to append. * @return a reference to this object. */
public AbstractStringBuilder append(StringBuffer sb) { return this.append((AbstractStringBuilder)sb); }
Since:1.8
/** * @since 1.8 */
AbstractStringBuilder append(AbstractStringBuilder asb) { if (asb == null) { return appendNull(); } int len = asb.length(); ensureCapacityInternal(count + len); if (getCoder() != asb.getCoder()) { inflate(); } asb.getBytes(value, count, coder); count += len; return this; } // Documentation in subclasses because of synchro difference @Override public AbstractStringBuilder append(CharSequence s) { if (s == null) { return appendNull(); } if (s instanceof String) { return this.append((String)s); } if (s instanceof AbstractStringBuilder) { return this.append((AbstractStringBuilder)s); } return this.append(s, 0, s.length()); } private AbstractStringBuilder appendNull() { ensureCapacityInternal(count + 4); int count = this.count; byte[] val = this.value; if (isLatin1()) { val[count++] = 'n'; val[count++] = 'u'; val[count++] = 'l'; val[count++] = 'l'; } else { count = StringUTF16.putCharsAt(val, count, 'n', 'u', 'l', 'l'); } this.count = count; return this; }
Appends a subsequence of the specified CharSequence to this sequence.

Characters of the argument s, starting at index start, are appended, in order, to the contents of this sequence up to the (exclusive) index end. The length of this sequence is increased by the value of end - start.

Let n be the length of this character sequence just prior to execution of the append method. Then the character at index k in this character sequence becomes equal to the character at index k in this sequence, if k is less than n; otherwise, it is equal to the character at index k+start-n in the argument s.

If s is null, then this method appends characters as if the s parameter was a sequence containing the four characters "null".

Params:
  • s – the sequence to append.
  • start – the starting index of the subsequence to be appended.
  • end – the end index of the subsequence to be appended.
Throws:
Returns: a reference to this object.
/** * Appends a subsequence of the specified {@code CharSequence} to this * sequence. * <p> * Characters of the argument {@code s}, starting at * index {@code start}, are appended, in order, to the contents of * this sequence up to the (exclusive) index {@code end}. The length * of this sequence is increased by the value of {@code end - start}. * <p> * Let <i>n</i> be the length of this character sequence just prior to * execution of the {@code append} method. Then the character at * index <i>k</i> in this character sequence becomes equal to the * character at index <i>k</i> in this sequence, if <i>k</i> is less than * <i>n</i>; otherwise, it is equal to the character at index * <i>k+start-n</i> in the argument {@code s}. * <p> * If {@code s} is {@code null}, then this method appends * characters as if the s parameter was a sequence containing the four * characters {@code "null"}. * * @param s the sequence to append. * @param start the starting index of the subsequence to be appended. * @param end the end index of the subsequence to be appended. * @return a reference to this object. * @throws IndexOutOfBoundsException if * {@code start} is negative, or * {@code start} is greater than {@code end} or * {@code end} is greater than {@code s.length()} */
@Override public AbstractStringBuilder append(CharSequence s, int start, int end) { if (s == null) { s = "null"; } checkRange(start, end, s.length()); int len = end - start; ensureCapacityInternal(count + len); if (s instanceof String) { appendChars((String)s, start, end); } else { appendChars(s, start, end); } return this; }
Appends the string representation of the char array argument to this sequence.

The characters of the array argument are appended, in order, to the contents of this sequence. The length of this sequence increases by the length of the argument.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(char[]), and the characters of that string were then appended to this character sequence.

Params:
  • str – the characters to be appended.
Returns: a reference to this object.
/** * Appends the string representation of the {@code char} array * argument to this sequence. * <p> * The characters of the array argument are appended, in order, to * the contents of this sequence. The length of this sequence * increases by the length of the argument. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(char[])}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param str the characters to be appended. * @return a reference to this object. */
public AbstractStringBuilder append(char[] str) { int len = str.length; ensureCapacityInternal(count + len); appendChars(str, 0, len); return this; }
Appends the string representation of a subarray of the char array argument to this sequence.

Characters of the char array str, starting at index offset, are appended, in order, to the contents of this sequence. The length of this sequence increases by the value of len.

The overall effect is exactly as if the arguments were converted to a string by the method String.valueOf(char[], int, int), and the characters of that string were then appended to this character sequence.

Params:
  • str – the characters to be appended.
  • offset – the index of the first char to append.
  • len – the number of chars to append.
Throws:
Returns: a reference to this object.
/** * Appends the string representation of a subarray of the * {@code char} array argument to this sequence. * <p> * Characters of the {@code char} array {@code str}, starting at * index {@code offset}, are appended, in order, to the contents * of this sequence. The length of this sequence increases * by the value of {@code len}. * <p> * The overall effect is exactly as if the arguments were converted * to a string by the method {@link String#valueOf(char[],int,int)}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param str the characters to be appended. * @param offset the index of the first {@code char} to append. * @param len the number of {@code char}s to append. * @return a reference to this object. * @throws IndexOutOfBoundsException * if {@code offset < 0} or {@code len < 0} * or {@code offset+len > str.length} */
public AbstractStringBuilder append(char[] str, int offset, int len) { int end = offset + len; checkRange(offset, end, str.length); ensureCapacityInternal(count + len); appendChars(str, offset, end); return this; }
Appends the string representation of the boolean argument to the sequence.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(boolean), and the characters of that string were then appended to this character sequence.

Params:
  • b – a boolean.
Returns: a reference to this object.
/** * Appends the string representation of the {@code boolean} * argument to the sequence. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(boolean)}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param b a {@code boolean}. * @return a reference to this object. */
public AbstractStringBuilder append(boolean b) { ensureCapacityInternal(count + (b ? 4 : 5)); int count = this.count; byte[] val = this.value; if (isLatin1()) { if (b) { val[count++] = 't'; val[count++] = 'r'; val[count++] = 'u'; val[count++] = 'e'; } else { val[count++] = 'f'; val[count++] = 'a'; val[count++] = 'l'; val[count++] = 's'; val[count++] = 'e'; } } else { if (b) { count = StringUTF16.putCharsAt(val, count, 't', 'r', 'u', 'e'); } else { count = StringUTF16.putCharsAt(val, count, 'f', 'a', 'l', 's', 'e'); } } this.count = count; return this; }
Appends the string representation of the char argument to this sequence.

The argument is appended to the contents of this sequence. The length of this sequence increases by 1.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(char), and the character in that string were then appended to this character sequence.

Params:
  • c – a char.
Returns: a reference to this object.
/** * Appends the string representation of the {@code char} * argument to this sequence. * <p> * The argument is appended to the contents of this sequence. * The length of this sequence increases by {@code 1}. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(char)}, * and the character in that string were then * {@link #append(String) appended} to this character sequence. * * @param c a {@code char}. * @return a reference to this object. */
@Override public AbstractStringBuilder append(char c) { ensureCapacityInternal(count + 1); if (isLatin1() && StringLatin1.canEncode(c)) { value[count++] = (byte)c; } else { if (isLatin1()) { inflate(); } StringUTF16.putCharSB(value, count++, c); } return this; }
Appends the string representation of the int argument to this sequence.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(int), and the characters of that string were then appended to this character sequence.

Params:
  • i – an int.
Returns: a reference to this object.
/** * Appends the string representation of the {@code int} * argument to this sequence. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(int)}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param i an {@code int}. * @return a reference to this object. */
public AbstractStringBuilder append(int i) { int count = this.count; int spaceNeeded = count + Integer.stringSize(i); ensureCapacityInternal(spaceNeeded); if (isLatin1()) { Integer.getChars(i, spaceNeeded, value); } else { StringUTF16.getChars(i, count, spaceNeeded, value); } this.count = spaceNeeded; return this; }
Appends the string representation of the long argument to this sequence.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(long), and the characters of that string were then appended to this character sequence.

Params:
  • l – a long.
Returns: a reference to this object.
/** * Appends the string representation of the {@code long} * argument to this sequence. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(long)}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param l a {@code long}. * @return a reference to this object. */
public AbstractStringBuilder append(long l) { int count = this.count; int spaceNeeded = count + Long.stringSize(l); ensureCapacityInternal(spaceNeeded); if (isLatin1()) { Long.getChars(l, spaceNeeded, value); } else { StringUTF16.getChars(l, count, spaceNeeded, value); } this.count = spaceNeeded; return this; }
Appends the string representation of the float argument to this sequence.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(float), and the characters of that string were then appended to this character sequence.

Params:
  • f – a float.
Returns: a reference to this object.
/** * Appends the string representation of the {@code float} * argument to this sequence. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(float)}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param f a {@code float}. * @return a reference to this object. */
public AbstractStringBuilder append(float f) { FloatingDecimal.appendTo(f,this); return this; }
Appends the string representation of the double argument to this sequence.

The overall effect is exactly as if the argument were converted to a string by the method String.valueOf(double), and the characters of that string were then appended to this character sequence.

Params:
  • d – a double.
Returns: a reference to this object.
/** * Appends the string representation of the {@code double} * argument to this sequence. * <p> * The overall effect is exactly as if the argument were converted * to a string by the method {@link String#valueOf(double)}, * and the characters of that string were then * {@link #append(String) appended} to this character sequence. * * @param d a {@code double}. * @return a reference to this object. */
public AbstractStringBuilder append(double d) { FloatingDecimal.appendTo(d,this); return this; }
Removes the characters in a substring of this sequence. The substring begins at the specified start and extends to the character at index end - 1 or to the end of the sequence if no such character exists. If start is equal to end, no changes are made.
Params:
  • start – The beginning index, inclusive.
  • end – The ending index, exclusive.
Throws:
Returns: This object.
/** * Removes the characters in a substring of this sequence. * The substring begins at the specified {@code start} and extends to * the character at index {@code end - 1} or to the end of the * sequence if no such character exists. If * {@code start} is equal to {@code end}, no changes are made. * * @param start The beginning index, inclusive. * @param end The ending index, exclusive. * @return This object. * @throws StringIndexOutOfBoundsException if {@code start} * is negative, greater than {@code length()}, or * greater than {@code end}. */
public AbstractStringBuilder delete(int start, int end) { int count = this.count; if (end > count) { end = count; } checkRangeSIOOBE(start, end, count); int len = end - start; if (len > 0) { shift(end, -len); this.count = count - len; } return this; }
Appends the string representation of the codePoint argument to this sequence.

The argument is appended to the contents of this sequence. The length of this sequence increases by Character.charCount(codePoint).

The overall effect is exactly as if the argument were converted to a char array by the method Character.toChars(int) and the character in that array were then appended to this character sequence.

Params:
  • codePoint – a Unicode code point
Throws:
Returns: a reference to this object.
/** * Appends the string representation of the {@code codePoint} * argument to this sequence. * * <p> The argument is appended to the contents of this sequence. * The length of this sequence increases by * {@link Character#charCount(int) Character.charCount(codePoint)}. * * <p> The overall effect is exactly as if the argument were * converted to a {@code char} array by the method * {@link Character#toChars(int)} and the character in that array * were then {@link #append(char[]) appended} to this character * sequence. * * @param codePoint a Unicode code point * @return a reference to this object. * @throws IllegalArgumentException if the specified * {@code codePoint} isn't a valid Unicode code point */
public AbstractStringBuilder appendCodePoint(int codePoint) { if (Character.isBmpCodePoint(codePoint)) { return append((char)codePoint); } return append(Character.toChars(codePoint)); }
Removes the char at the specified position in this sequence. This sequence is shortened by one char.

Note: If the character at the given index is a supplementary character, this method does not remove the entire character. If correct handling of supplementary characters is required, determine the number of chars to remove by calling Character.charCount(thisSequence.codePointAt(index)), where thisSequence is this sequence.

Params:
  • index – Index of char to remove
Throws:
Returns: This object.
/** * Removes the {@code char} at the specified position in this * sequence. This sequence is shortened by one {@code char}. * * <p>Note: If the character at the given index is a supplementary * character, this method does not remove the entire character. If * correct handling of supplementary characters is required, * determine the number of {@code char}s to remove by calling * {@code Character.charCount(thisSequence.codePointAt(index))}, * where {@code thisSequence} is this sequence. * * @param index Index of {@code char} to remove * @return This object. * @throws StringIndexOutOfBoundsException if the {@code index} * is negative or greater than or equal to * {@code length()}. */
public AbstractStringBuilder deleteCharAt(int index) { checkIndex(index, count); shift(index + 1, -1); count--; return this; }
Replaces the characters in a substring of this sequence with characters in the specified String. The substring begins at the specified start and extends to the character at index end - 1 or to the end of the sequence if no such character exists. First the characters in the substring are removed and then the specified String is inserted at start. (This sequence will be lengthened to accommodate the specified String if necessary.)
Params:
  • start – The beginning index, inclusive.
  • end – The ending index, exclusive.
  • str – String that will replace previous contents.
Throws:
Returns: This object.
/** * Replaces the characters in a substring of this sequence * with characters in the specified {@code String}. The substring * begins at the specified {@code start} and extends to the character * at index {@code end - 1} or to the end of the * sequence if no such character exists. First the * characters in the substring are removed and then the specified * {@code String} is inserted at {@code start}. (This * sequence will be lengthened to accommodate the * specified String if necessary.) * * @param start The beginning index, inclusive. * @param end The ending index, exclusive. * @param str String that will replace previous contents. * @return This object. * @throws StringIndexOutOfBoundsException if {@code start} * is negative, greater than {@code length()}, or * greater than {@code end}. */
public AbstractStringBuilder replace(int start, int end, String str) { int count = this.count; if (end > count) { end = count; } checkRangeSIOOBE(start, end, count); int len = str.length(); int newCount = count + len - (end - start); ensureCapacityInternal(newCount); shift(end, newCount - count); this.count = newCount; putStringAt(start, str); return this; }
Returns a new String that contains a subsequence of characters currently contained in this character sequence. The substring begins at the specified index and extends to the end of this sequence.
Params:
  • start – The beginning index, inclusive.
Throws:
Returns: The new string.
/** * Returns a new {@code String} that contains a subsequence of * characters currently contained in this character sequence. The * substring begins at the specified index and extends to the end of * this sequence. * * @param start The beginning index, inclusive. * @return The new string. * @throws StringIndexOutOfBoundsException if {@code start} is * less than zero, or greater than the length of this object. */
public String substring(int start) { return substring(start, count); }
Returns a new character sequence that is a subsequence of this sequence.

An invocation of this method of the form


sb.subSequence(begin, end)
behaves in exactly the same way as the invocation

sb.substring(begin, end)
This method is provided so that this class can implement the CharSequence interface.
Params:
  • start – the start index, inclusive.
  • end – the end index, exclusive.
Throws:
Returns: the specified subsequence.
/** * Returns a new character sequence that is a subsequence of this sequence. * * <p> An invocation of this method of the form * * <pre>{@code * sb.subSequence(begin, end)}</pre> * * behaves in exactly the same way as the invocation * * <pre>{@code * sb.substring(begin, end)}</pre> * * This method is provided so that this class can * implement the {@link CharSequence} interface. * * @param start the start index, inclusive. * @param end the end index, exclusive. * @return the specified subsequence. * * @throws IndexOutOfBoundsException * if {@code start} or {@code end} are negative, * if {@code end} is greater than {@code length()}, * or if {@code start} is greater than {@code end} */
@Override public CharSequence subSequence(int start, int end) { return substring(start, end); }
Returns a new String that contains a subsequence of characters currently contained in this sequence. The substring begins at the specified start and extends to the character at index end - 1.
Params:
  • start – The beginning index, inclusive.
  • end – The ending index, exclusive.
Throws:
Returns: The new string.
/** * Returns a new {@code String} that contains a subsequence of * characters currently contained in this sequence. The * substring begins at the specified {@code start} and * extends to the character at index {@code end - 1}. * * @param start The beginning index, inclusive. * @param end The ending index, exclusive. * @return The new string. * @throws StringIndexOutOfBoundsException if {@code start} * or {@code end} are negative or greater than * {@code length()}, or {@code start} is * greater than {@code end}. */
public String substring(int start, int end) { checkRangeSIOOBE(start, end, count); if (isLatin1()) { return StringLatin1.newString(value, start, end - start); } return StringUTF16.newString(value, start, end - start); } private void shift(int offset, int n) { System.arraycopy(value, offset << coder, value, (offset + n) << coder, (count - offset) << coder); }
Inserts the string representation of a subarray of the str array argument into this sequence. The subarray begins at the specified offset and extends len chars. The characters of the subarray are inserted into this sequence at the position indicated by index. The length of this sequence increases by len chars.
Params:
  • index – position at which to insert subarray.
  • str – A char array.
  • offset – the index of the first char in subarray to be inserted.
  • len – the number of chars in the subarray to be inserted.
Throws:
  • StringIndexOutOfBoundsException – if index is negative or greater than length(), or offset or len are negative, or (offset+len) is greater than str.length.
Returns: This object
/** * Inserts the string representation of a subarray of the {@code str} * array argument into this sequence. The subarray begins at the * specified {@code offset} and extends {@code len} {@code char}s. * The characters of the subarray are inserted into this sequence at * the position indicated by {@code index}. The length of this * sequence increases by {@code len} {@code char}s. * * @param index position at which to insert subarray. * @param str A {@code char} array. * @param offset the index of the first {@code char} in subarray to * be inserted. * @param len the number of {@code char}s in the subarray to * be inserted. * @return This object * @throws StringIndexOutOfBoundsException if {@code index} * is negative or greater than {@code length()}, or * {@code offset} or {@code len} are negative, or * {@code (offset+len)} is greater than * {@code str.length}. */
public AbstractStringBuilder insert(int index, char[] str, int offset, int len) { checkOffset(index, count); checkRangeSIOOBE(offset, offset + len, str.length); ensureCapacityInternal(count + len); shift(index, len); count += len; putCharsAt(index, str, offset, offset + len); return this; }
Inserts the string representation of the Object argument into this character sequence.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(Object), and the characters of that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • obj – an Object.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the {@code Object} * argument into this character sequence. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(Object)}, * and the characters of that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param obj an {@code Object}. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, Object obj) { return insert(offset, String.valueOf(obj)); }
Inserts the string into this character sequence.

The characters of the String argument are inserted, in order, into this sequence at the indicated offset, moving up any characters originally above that position and increasing the length of this sequence by the length of the argument. If str is null, then the four characters "null" are inserted into this sequence.

The character at index k in the new character sequence is equal to:

  • the character at index k in the old character sequence, if k is less than offset
  • the character at index k-offset in the argument str, if k is not less than offset but is less than offset+str.length()
  • the character at index k-str.length() in the old character sequence, if k is not less than offset+str.length()

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • str – a string.
Throws:
Returns: a reference to this object.
/** * Inserts the string into this character sequence. * <p> * The characters of the {@code String} argument are inserted, in * order, into this sequence at the indicated offset, moving up any * characters originally above that position and increasing the length * of this sequence by the length of the argument. If * {@code str} is {@code null}, then the four characters * {@code "null"} are inserted into this sequence. * <p> * The character at index <i>k</i> in the new character sequence is * equal to: * <ul> * <li>the character at index <i>k</i> in the old character sequence, if * <i>k</i> is less than {@code offset} * <li>the character at index <i>k</i>{@code -offset} in the * argument {@code str}, if <i>k</i> is not less than * {@code offset} but is less than {@code offset+str.length()} * <li>the character at index <i>k</i>{@code -str.length()} in the * old character sequence, if <i>k</i> is not less than * {@code offset+str.length()} * </ul><p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param str a string. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, String str) { checkOffset(offset, count); if (str == null) { str = "null"; } int len = str.length(); ensureCapacityInternal(count + len); shift(offset, len); count += len; putStringAt(offset, str); return this; }
Inserts the string representation of the char array argument into this sequence.

The characters of the array argument are inserted into the contents of this sequence at the position indicated by offset. The length of this sequence increases by the length of the argument.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(char[]), and the characters of that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • str – a character array.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the {@code char} array * argument into this sequence. * <p> * The characters of the array argument are inserted into the * contents of this sequence at the position indicated by * {@code offset}. The length of this sequence increases by * the length of the argument. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(char[])}, * and the characters of that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param str a character array. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, char[] str) { checkOffset(offset, count); int len = str.length; ensureCapacityInternal(count + len); shift(offset, len); count += len; putCharsAt(offset, str, 0, len); return this; }
Inserts the specified CharSequence into this sequence.

The characters of the CharSequence argument are inserted, in order, into this sequence at the indicated offset, moving up any characters originally above that position and increasing the length of this sequence by the length of the argument s.

The result of this method is exactly the same as if it were an invocation of this object's insert(dstOffset, s, 0, s.length()) method.

If s is null, then the four characters "null" are inserted into this sequence.

Params:
  • dstOffset – the offset.
  • s – the sequence to be inserted
Throws:
Returns: a reference to this object.
/** * Inserts the specified {@code CharSequence} into this sequence. * <p> * The characters of the {@code CharSequence} argument are inserted, * in order, into this sequence at the indicated offset, moving up * any characters originally above that position and increasing the length * of this sequence by the length of the argument s. * <p> * The result of this method is exactly the same as if it were an * invocation of this object's * {@link #insert(int,CharSequence,int,int) insert}(dstOffset, s, 0, s.length()) * method. * * <p>If {@code s} is {@code null}, then the four characters * {@code "null"} are inserted into this sequence. * * @param dstOffset the offset. * @param s the sequence to be inserted * @return a reference to this object. * @throws IndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int dstOffset, CharSequence s) { if (s == null) { s = "null"; } return this.insert(dstOffset, s, 0, s.length()); }
Inserts a subsequence of the specified CharSequence into this sequence.

The subsequence of the argument s specified by start and end are inserted, in order, into this sequence at the specified destination offset, moving up any characters originally above that position. The length of this sequence is increased by end - start.

The character at index k in this sequence becomes equal to:

  • the character at index k in this sequence, if k is less than dstOffset
  • the character at index k+start-dstOffset in the argument s, if k is greater than or equal to dstOffset but is less than dstOffset+end-start
  • the character at index k-(end-start) in this sequence, if k is greater than or equal to dstOffset+end-start

The dstOffset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

The start argument must be nonnegative, and not greater than end.

The end argument must be greater than or equal to start, and less than or equal to the length of s.

If s is null, then this method inserts characters as if the s parameter was a sequence containing the four characters "null".

Params:
  • dstOffset – the offset in this sequence.
  • s – the sequence to be inserted.
  • start – the starting index of the subsequence to be inserted.
  • end – the end index of the subsequence to be inserted.
Throws:
  • IndexOutOfBoundsException – if dstOffset is negative or greater than this.length(), or start or end are negative, or start is greater than end or end is greater than s.length()
Returns: a reference to this object.
/** * Inserts a subsequence of the specified {@code CharSequence} into * this sequence. * <p> * The subsequence of the argument {@code s} specified by * {@code start} and {@code end} are inserted, * in order, into this sequence at the specified destination offset, moving * up any characters originally above that position. The length of this * sequence is increased by {@code end - start}. * <p> * The character at index <i>k</i> in this sequence becomes equal to: * <ul> * <li>the character at index <i>k</i> in this sequence, if * <i>k</i> is less than {@code dstOffset} * <li>the character at index <i>k</i>{@code +start-dstOffset} in * the argument {@code s}, if <i>k</i> is greater than or equal to * {@code dstOffset} but is less than {@code dstOffset+end-start} * <li>the character at index <i>k</i>{@code -(end-start)} in this * sequence, if <i>k</i> is greater than or equal to * {@code dstOffset+end-start} * </ul><p> * The {@code dstOffset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * <p>The start argument must be nonnegative, and not greater than * {@code end}. * <p>The end argument must be greater than or equal to * {@code start}, and less than or equal to the length of s. * * <p>If {@code s} is {@code null}, then this method inserts * characters as if the s parameter was a sequence containing the four * characters {@code "null"}. * * @param dstOffset the offset in this sequence. * @param s the sequence to be inserted. * @param start the starting index of the subsequence to be inserted. * @param end the end index of the subsequence to be inserted. * @return a reference to this object. * @throws IndexOutOfBoundsException if {@code dstOffset} * is negative or greater than {@code this.length()}, or * {@code start} or {@code end} are negative, or * {@code start} is greater than {@code end} or * {@code end} is greater than {@code s.length()} */
public AbstractStringBuilder insert(int dstOffset, CharSequence s, int start, int end) { if (s == null) { s = "null"; } checkOffset(dstOffset, count); checkRange(start, end, s.length()); int len = end - start; ensureCapacityInternal(count + len); shift(dstOffset, len); count += len; if (s instanceof String) { putStringAt(dstOffset, (String) s, start, end); } else { putCharsAt(dstOffset, s, start, end); } return this; }
Inserts the string representation of the boolean argument into this sequence.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(boolean), and the characters of that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • b – a boolean.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the {@code boolean} * argument into this sequence. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(boolean)}, * and the characters of that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param b a {@code boolean}. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, boolean b) { return insert(offset, String.valueOf(b)); }
Inserts the string representation of the char argument into this sequence.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(char), and the character in that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • c – a char.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the {@code char} * argument into this sequence. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(char)}, * and the character in that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param c a {@code char}. * @return a reference to this object. * @throws IndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, char c) { checkOffset(offset, count); ensureCapacityInternal(count + 1); shift(offset, 1); count += 1; if (isLatin1() && StringLatin1.canEncode(c)) { value[offset] = (byte)c; } else { if (isLatin1()) { inflate(); } StringUTF16.putCharSB(value, offset, c); } return this; }
Inserts the string representation of the second int argument into this sequence.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(int), and the characters of that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • i – an int.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the second {@code int} * argument into this sequence. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(int)}, * and the characters of that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param i an {@code int}. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, int i) { return insert(offset, String.valueOf(i)); }
Inserts the string representation of the long argument into this sequence.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(long), and the characters of that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • l – a long.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the {@code long} * argument into this sequence. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(long)}, * and the characters of that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param l a {@code long}. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, long l) { return insert(offset, String.valueOf(l)); }
Inserts the string representation of the float argument into this sequence.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(float), and the characters of that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • f – a float.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the {@code float} * argument into this sequence. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(float)}, * and the characters of that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param f a {@code float}. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, float f) { return insert(offset, String.valueOf(f)); }
Inserts the string representation of the double argument into this sequence.

The overall effect is exactly as if the second argument were converted to a string by the method String.valueOf(double), and the characters of that string were then inserted into this character sequence at the indicated offset.

The offset argument must be greater than or equal to 0, and less than or equal to the length of this sequence.

Params:
  • offset – the offset.
  • d – a double.
Throws:
Returns: a reference to this object.
/** * Inserts the string representation of the {@code double} * argument into this sequence. * <p> * The overall effect is exactly as if the second argument were * converted to a string by the method {@link String#valueOf(double)}, * and the characters of that string were then * {@link #insert(int,String) inserted} into this character * sequence at the indicated offset. * <p> * The {@code offset} argument must be greater than or equal to * {@code 0}, and less than or equal to the {@linkplain #length() length} * of this sequence. * * @param offset the offset. * @param d a {@code double}. * @return a reference to this object. * @throws StringIndexOutOfBoundsException if the offset is invalid. */
public AbstractStringBuilder insert(int offset, double d) { return insert(offset, String.valueOf(d)); }
Returns the index within this string of the first occurrence of the specified substring.

The returned index is the smallest value k for which:


this.toString().startsWith(str, k)
If no such value of k exists, then -1 is returned.
Params:
  • str – the substring to search for.
Returns: the index of the first occurrence of the specified substring, or -1 if there is no such occurrence.
/** * Returns the index within this string of the first occurrence of the * specified substring. * * <p>The returned index is the smallest value {@code k} for which: * <pre>{@code * this.toString().startsWith(str, k) * }</pre> * If no such value of {@code k} exists, then {@code -1} is returned. * * @param str the substring to search for. * @return the index of the first occurrence of the specified substring, * or {@code -1} if there is no such occurrence. */
public int indexOf(String str) { return indexOf(str, 0); }
Returns the index within this string of the first occurrence of the specified substring, starting at the specified index.

The returned index is the smallest value k for which:


    k >= Math.min(fromIndex, this.length()) &&
                  this.toString().startsWith(str, k)
If no such value of k exists, then -1 is returned.
Params:
  • str – the substring to search for.
  • fromIndex – the index from which to start the search.
Returns: the index of the first occurrence of the specified substring, starting at the specified index, or -1 if there is no such occurrence.
/** * Returns the index within this string of the first occurrence of the * specified substring, starting at the specified index. * * <p>The returned index is the smallest value {@code k} for which: * <pre>{@code * k >= Math.min(fromIndex, this.length()) && * this.toString().startsWith(str, k) * }</pre> * If no such value of {@code k} exists, then {@code -1} is returned. * * @param str the substring to search for. * @param fromIndex the index from which to start the search. * @return the index of the first occurrence of the specified substring, * starting at the specified index, * or {@code -1} if there is no such occurrence. */
public int indexOf(String str, int fromIndex) { return String.indexOf(value, coder, count, str, fromIndex); }
Returns the index within this string of the last occurrence of the specified substring. The last occurrence of the empty string "" is considered to occur at the index value this.length().

The returned index is the largest value k for which:


this.toString().startsWith(str, k)
If no such value of k exists, then -1 is returned.
Params:
  • str – the substring to search for.
Returns: the index of the last occurrence of the specified substring, or -1 if there is no such occurrence.
/** * Returns the index within this string of the last occurrence of the * specified substring. The last occurrence of the empty string "" is * considered to occur at the index value {@code this.length()}. * * <p>The returned index is the largest value {@code k} for which: * <pre>{@code * this.toString().startsWith(str, k) * }</pre> * If no such value of {@code k} exists, then {@code -1} is returned. * * @param str the substring to search for. * @return the index of the last occurrence of the specified substring, * or {@code -1} if there is no such occurrence. */
public int lastIndexOf(String str) { return lastIndexOf(str, count); }
Returns the index within this string of the last occurrence of the specified substring, searching backward starting at the specified index.

The returned index is the largest value k for which:


    k <= Math.min(fromIndex, this.length()) &&
                  this.toString().startsWith(str, k)
If no such value of k exists, then -1 is returned.
Params:
  • str – the substring to search for.
  • fromIndex – the index to start the search from.
Returns: the index of the last occurrence of the specified substring, searching backward from the specified index, or -1 if there is no such occurrence.
/** * Returns the index within this string of the last occurrence of the * specified substring, searching backward starting at the specified index. * * <p>The returned index is the largest value {@code k} for which: * <pre>{@code * k <= Math.min(fromIndex, this.length()) && * this.toString().startsWith(str, k) * }</pre> * If no such value of {@code k} exists, then {@code -1} is returned. * * @param str the substring to search for. * @param fromIndex the index to start the search from. * @return the index of the last occurrence of the specified substring, * searching backward from the specified index, * or {@code -1} if there is no such occurrence. */
public int lastIndexOf(String str, int fromIndex) { return String.lastIndexOf(value, coder, count, str, fromIndex); }
Causes this character sequence to be replaced by the reverse of the sequence. If there are any surrogate pairs included in the sequence, these are treated as single characters for the reverse operation. Thus, the order of the high-low surrogates is never reversed. Let n be the character length of this character sequence (not the length in char values) just prior to execution of the reverse method. Then the character at index k in the new character sequence is equal to the character at index n-k-1 in the old character sequence.

Note that the reverse operation may result in producing surrogate pairs that were unpaired low-surrogates and high-surrogates before the operation. For example, reversing "\u005CuDC00\u005CuD800" produces "\u005CuD800\u005CuDC00" which is a valid surrogate pair.

Returns: a reference to this object.
/** * Causes this character sequence to be replaced by the reverse of * the sequence. If there are any surrogate pairs included in the * sequence, these are treated as single characters for the * reverse operation. Thus, the order of the high-low surrogates * is never reversed. * * Let <i>n</i> be the character length of this character sequence * (not the length in {@code char} values) just prior to * execution of the {@code reverse} method. Then the * character at index <i>k</i> in the new character sequence is * equal to the character at index <i>n-k-1</i> in the old * character sequence. * * <p>Note that the reverse operation may result in producing * surrogate pairs that were unpaired low-surrogates and * high-surrogates before the operation. For example, reversing * "\u005CuDC00\u005CuD800" produces "\u005CuD800\u005CuDC00" which is * a valid surrogate pair. * * @return a reference to this object. */
public AbstractStringBuilder reverse() { byte[] val = this.value; int count = this.count; int n = count - 1; if (isLatin1()) { for (int j = (n-1) >> 1; j >= 0; j--) { int k = n - j; byte cj = val[j]; val[j] = val[k]; val[k] = cj; } } else { StringUTF16.reverse(val, count); } return this; }
Returns a string representing the data in this sequence. A new String object is allocated and initialized to contain the character sequence currently represented by this object. This String is then returned. Subsequent changes to this sequence do not affect the contents of the String.
Returns: a string representation of this sequence of characters.
/** * Returns a string representing the data in this sequence. * A new {@code String} object is allocated and initialized to * contain the character sequence currently represented by this * object. This {@code String} is then returned. Subsequent * changes to this sequence do not affect the contents of the * {@code String}. * * @return a string representation of this sequence of characters. */
@Override public abstract String toString();
{@inheritDoc}
Since:9
/** * {@inheritDoc} * @since 9 */
@Override public IntStream chars() { // Reuse String-based spliterator. This requires a supplier to // capture the value and count when the terminal operation is executed return StreamSupport.intStream( () -> { // The combined set of field reads are not atomic and thread // safe but bounds checks will ensure no unsafe reads from // the byte array byte[] val = this.value; int count = this.count; byte coder = this.coder; return coder == LATIN1 ? new StringLatin1.CharsSpliterator(val, 0, count, 0) : new StringUTF16.CharsSpliterator(val, 0, count, 0); }, Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED, false); }
{@inheritDoc}
Since:9
/** * {@inheritDoc} * @since 9 */
@Override public IntStream codePoints() { // Reuse String-based spliterator. This requires a supplier to // capture the value and count when the terminal operation is executed return StreamSupport.intStream( () -> { // The combined set of field reads are not atomic and thread // safe but bounds checks will ensure no unsafe reads from // the byte array byte[] val = this.value; int count = this.count; byte coder = this.coder; return coder == LATIN1 ? new StringLatin1.CharsSpliterator(val, 0, count, 0) : new StringUTF16.CodePointsSpliterator(val, 0, count, 0); }, Spliterator.ORDERED, false); }
Needed by String for the contentEquals method.
/** * Needed by {@code String} for the contentEquals method. */
final byte[] getValue() { return value; } /* * Invoker guarantees it is in UTF16 (inflate itself for asb), if two * coders are different and the dstBegin has enough space * * @param dstBegin the char index, not offset of byte[] * @param coder the coder of dst[] */ void getBytes(byte[] dst, int dstBegin, byte coder) { if (this.coder == coder) { System.arraycopy(value, 0, dst, dstBegin << coder, count << coder); } else { // this.coder == LATIN && coder == UTF16 StringLatin1.inflate(value, 0, dst, dstBegin, count); } } /* for readObject() */ void initBytes(char[] value, int off, int len) { if (String.COMPACT_STRINGS) { this.value = StringUTF16.compress(value, off, len); if (this.value != null) { this.coder = LATIN1; return; } } this.coder = UTF16; this.value = StringUTF16.toBytes(value, off, len); } final byte getCoder() { return COMPACT_STRINGS ? coder : UTF16; } final boolean isLatin1() { return COMPACT_STRINGS && coder == LATIN1; } private final void putCharsAt(int index, char[] s, int off, int end) { if (isLatin1()) { byte[] val = this.value; for (int i = off, j = index; i < end; i++) { char c = s[i]; if (StringLatin1.canEncode(c)) { val[j++] = (byte)c; } else { inflate(); StringUTF16.putCharsSB(this.value, j, s, i, end); return; } } } else { StringUTF16.putCharsSB(this.value, index, s, off, end); } } private final void putCharsAt(int index, CharSequence s, int off, int end) { if (isLatin1()) { byte[] val = this.value; for (int i = off, j = index; i < end; i++) { char c = s.charAt(i); if (StringLatin1.canEncode(c)) { val[j++] = (byte)c; } else { inflate(); StringUTF16.putCharsSB(this.value, j, s, i, end); return; } } } else { StringUTF16.putCharsSB(this.value, index, s, off, end); } } private void putStringAt(int index, String str, int off, int end) { if (getCoder() != str.coder()) { inflate(); } str.getBytes(value, off, index, coder, end - off); } private void putStringAt(int index, String str) { putStringAt(index, str, 0, str.length()); } private final void appendChars(char[] s, int off, int end) { int count = this.count; if (isLatin1()) { byte[] val = this.value; for (int i = off, j = count; i < end; i++) { char c = s[i]; if (StringLatin1.canEncode(c)) { val[j++] = (byte)c; } else { this.count = count = j; inflate(); StringUTF16.putCharsSB(this.value, j, s, i, end); this.count = count + end - i; return; } } } else { StringUTF16.putCharsSB(this.value, count, s, off, end); } this.count = count + end - off; } private final void appendChars(String s, int off, int end) { if (isLatin1()) { if (s.isLatin1()) { System.arraycopy(s.value(), off, this.value, this.count, end - off); } else { // We might need to inflate, but do it as late as possible since // the range of characters we're copying might all be latin1 byte[] val = this.value; for (int i = off, j = count; i < end; i++) { char c = s.charAt(i); if (StringLatin1.canEncode(c)) { val[j++] = (byte) c; } else { count = j; inflate(); System.arraycopy(s.value(), i << UTF16, this.value, j << UTF16, (end - i) << UTF16); count += end - i; return; } } } } else if (s.isLatin1()) { StringUTF16.putCharsSB(this.value, this.count, s, off, end); } else { // both UTF16 System.arraycopy(s.value(), off << UTF16, this.value, this.count << UTF16, (end - off) << UTF16); } count += end - off; } private final void appendChars(CharSequence s, int off, int end) { if (isLatin1()) { byte[] val = this.value; for (int i = off, j = count; i < end; i++) { char c = s.charAt(i); if (StringLatin1.canEncode(c)) { val[j++] = (byte)c; } else { count = j; inflate(); StringUTF16.putCharsSB(this.value, j, s, i, end); count += end - i; return; } } } else { StringUTF16.putCharsSB(this.value, count, s, off, end); } count += end - off; } /* IndexOutOfBoundsException, if out of bounds */ private static void checkRange(int start, int end, int len) { if (start < 0 || start > end || end > len) { throw new IndexOutOfBoundsException( "start " + start + ", end " + end + ", length " + len); } } /* StringIndexOutOfBoundsException, if out of bounds */ private static void checkRangeSIOOBE(int start, int end, int len) { if (start < 0 || start > end || end > len) { throw new StringIndexOutOfBoundsException( "start " + start + ", end " + end + ", length " + len); } } }