/*
 * Copyright (c) 1994, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package java.lang;

import java.lang.annotation.Native;
import java.math.*;
import java.util.Objects;
import jdk.internal.HotSpotIntrinsicCandidate;

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

The Long class wraps a value of the primitive type 
long in an object. An object of type Long contains a single field whose type is long. 
 In addition, this class provides several methods for converting a long to a String and a String to a 
long, as well as other constants and methods useful when dealing with a long. 
Implementation note: The implementations of the "bit twiddling" methods (such as highestOneBit and numberOfTrailingZeros) are based on material from Henry S. Warren, Jr.'s Hacker's
Delight, (Addison Wesley, 2002).
Author:
 Lee Boynton,  Arthur van Hoff,  Josh Bloch,  Joseph D. Darcy
Since:
  1.0/**
 * The {@code Long} class wraps a value of the primitive type {@code
 * long} in an object. An object of type {@code Long} contains a
 * single field whose type is {@code long}.
 *
 * <p> In addition, this class provides several methods for converting
 * a {@code long} to a {@code String} and a {@code String} to a {@code
 * long}, as well as other constants and methods useful when dealing
 * with a {@code long}.
 *
 * <p>Implementation note: The implementations of the "bit twiddling"
 * methods (such as {@link #highestOneBit(long) highestOneBit} and
 * {@link #numberOfTrailingZeros(long) numberOfTrailingZeros}) are
 * based on material from Henry S. Warren, Jr.'s <i>Hacker's
 * Delight</i>, (Addison Wesley, 2002).
 *
 * @author  Lee Boynton
 * @author  Arthur van Hoff
 * @author  Josh Bloch
 * @author  Joseph D. Darcy
 * @since   1.0
 */
public final class Long extends Number implements Comparable<Long> {
    
A constant holding the minimum value a long can have, -263.
/**
     * A constant holding the minimum value a {@code long} can
     * have, -2<sup>63</sup>.
     */
    @Native public static final long MIN_VALUE = 0x8000000000000000L;

    
A constant holding the maximum value a long can have, 263-1.
/**
     * A constant holding the maximum value a {@code long} can
     * have, 2<sup>63</sup>-1.
     */
    @Native public static final long MAX_VALUE = 0x7fffffffffffffffL;

    
The Class instance representing the primitive type long. 
Since:
  1.1/**
     * The {@code Class} instance representing the primitive type
     * {@code long}.
     *
     * @since   1.1
     */
    @SuppressWarnings("unchecked")
    public static final Class<Long>     TYPE = (Class<Long>) Class.getPrimitiveClass("long");

    
Returns a string representation of the first argument in the
radix specified by the second argument.
If the radix is smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX, then the radix 10 is used instead. 
If the first argument is negative, the first element of the result is the ASCII minus sign '-' ('\u005Cu002d'). If the first argument is not negative, no sign character appears in the result. 
The remaining characters of the result represent the magnitude of the first argument. If the magnitude is zero, it is represented by a single zero character '0' ('\u005Cu0030'); otherwise, the first character of the representation of the magnitude will not be the zero character. The following ASCII characters are used as digits: 
 0123456789abcdefghijklmnopqrstuvwxyz 
 These are '\u005Cu0030' through '\u005Cu0039' and '\u005Cu0061' through '\u005Cu007a'. If radix is N, then the first N of these characters
are used as radix-N digits in the order shown. Thus, the digits for hexadecimal (radix 16) are 0123456789abcdef. If uppercase letters are desired, the String.toUpperCase() method may be called on the result: 
 Long.toString(n, 16).toUpperCase() 
Params:
i –  a long to be converted to a string.
radix –   the radix to use in the string representation.
See Also:
Character.MAX_RADIX
Character.MIN_RADIX
Returns:
 a string representation of the argument in the specified radix./**
     * Returns a string representation of the first argument in the
     * radix specified by the second argument.
     *
     * <p>If the radix is smaller than {@code Character.MIN_RADIX}
     * or larger than {@code Character.MAX_RADIX}, then the radix
     * {@code 10} is used instead.
     *
     * <p>If the first argument is negative, the first element of the
     * result is the ASCII minus sign {@code '-'}
     * ({@code '\u005Cu002d'}). If the first argument is not
     * negative, no sign character appears in the result.
     *
     * <p>The remaining characters of the result represent the magnitude
     * of the first argument. If the magnitude is zero, it is
     * represented by a single zero character {@code '0'}
     * ({@code '\u005Cu0030'}); otherwise, the first character of
     * the representation of the magnitude will not be the zero
     * character.  The following ASCII characters are used as digits:
     *
     * <blockquote>
     *   {@code 0123456789abcdefghijklmnopqrstuvwxyz}
     * </blockquote>
     *
     * These are {@code '\u005Cu0030'} through
     * {@code '\u005Cu0039'} and {@code '\u005Cu0061'} through
     * {@code '\u005Cu007a'}. If {@code radix} is
     * <var>N</var>, then the first <var>N</var> of these characters
     * are used as radix-<var>N</var> digits in the order shown. Thus,
     * the digits for hexadecimal (radix 16) are
     * {@code 0123456789abcdef}. If uppercase letters are
     * desired, the {@link java.lang.String#toUpperCase()} method may
     * be called on the result:
     *
     * <blockquote>
     *  {@code Long.toString(n, 16).toUpperCase()}
     * </blockquote>
     *
     * @param   i       a {@code long} to be converted to a string.
     * @param   radix   the radix to use in the string representation.
     * @return  a string representation of the argument in the specified radix.
     * @see     java.lang.Character#MAX_RADIX
     * @see     java.lang.Character#MIN_RADIX
     */
    public static String toString(long i, int radix) {
        if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX)
            radix = 10;
        if (radix == 10)
            return toString(i);

        if (COMPACT_STRINGS) {
            byte[] buf = new byte[65];
            int charPos = 64;
            boolean negative = (i < 0);

            if (!negative) {
                i = -i;
            }

            while (i <= -radix) {
                buf[charPos--] = (byte)Integer.digits[(int)(-(i % radix))];
                i = i / radix;
            }
            buf[charPos] = (byte)Integer.digits[(int)(-i)];

            if (negative) {
                buf[--charPos] = '-';
            }
            return StringLatin1.newString(buf, charPos, (65 - charPos));
        }
        return toStringUTF16(i, radix);
    }

    private static String toStringUTF16(long i, int radix) {
        byte[] buf = new byte[65 * 2];
        int charPos = 64;
        boolean negative = (i < 0);
        if (!negative) {
            i = -i;
        }
        while (i <= -radix) {
            StringUTF16.putChar(buf, charPos--, Integer.digits[(int)(-(i % radix))]);
            i = i / radix;
        }
        StringUTF16.putChar(buf, charPos, Integer.digits[(int)(-i)]);
        if (negative) {
            StringUTF16.putChar(buf, --charPos, '-');
        }
        return StringUTF16.newString(buf, charPos, (65 - charPos));
    }

    
Returns a string representation of the first argument as an
unsigned integer value in the radix specified by the second
argument.
If the radix is smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX, then the radix 10 is used instead. 
Note that since the first argument is treated as an unsigned
value, no leading sign character is printed.
If the magnitude is zero, it is represented by a single zero character '0' ('\u005Cu0030'); otherwise, the first character of the representation of the magnitude will not be the zero character. 
The behavior of radixes and the characters used as digits are the same as toString. 
Params:
i –       an integer to be converted to an unsigned string.
radix –   the radix to use in the string representation.
See Also:
toString(long, int)
Returns:
 an unsigned string representation of the argument in the specified radix.
Since:
1.8/**
     * Returns a string representation of the first argument as an
     * unsigned integer value in the radix specified by the second
     * argument.
     *
     * <p>If the radix is smaller than {@code Character.MIN_RADIX}
     * or larger than {@code Character.MAX_RADIX}, then the radix
     * {@code 10} is used instead.
     *
     * <p>Note that since the first argument is treated as an unsigned
     * value, no leading sign character is printed.
     *
     * <p>If the magnitude is zero, it is represented by a single zero
     * character {@code '0'} ({@code '\u005Cu0030'}); otherwise,
     * the first character of the representation of the magnitude will
     * not be the zero character.
     *
     * <p>The behavior of radixes and the characters used as digits
     * are the same as {@link #toString(long, int) toString}.
     *
     * @param   i       an integer to be converted to an unsigned string.
     * @param   radix   the radix to use in the string representation.
     * @return  an unsigned string representation of the argument in the specified radix.
     * @see     #toString(long, int)
     * @since 1.8
     */
    public static String toUnsignedString(long i, int radix) {
        if (i >= 0)
            return toString(i, radix);
        else {
            switch (radix) {
            case 2:
                return toBinaryString(i);

            case 4:
                return toUnsignedString0(i, 2);

            case 8:
                return toOctalString(i);

            case 10:
                /*
                 * We can get the effect of an unsigned division by 10
                 * on a long value by first shifting right, yielding a
                 * positive value, and then dividing by 5.  This
                 * allows the last digit and preceding digits to be
                 * isolated more quickly than by an initial conversion
                 * to BigInteger.
                 */
                long quot = (i >>> 1) / 5;
                long rem = i - quot * 10;
                return toString(quot) + rem;

            case 16:
                return toHexString(i);

            case 32:
                return toUnsignedString0(i, 5);

            default:
                return toUnsignedBigInteger(i).toString(radix);
            }
        }
    }

    
Return a BigInteger equal to the unsigned value of the
argument.
/**
     * Return a BigInteger equal to the unsigned value of the
     * argument.
     */
    private static BigInteger toUnsignedBigInteger(long i) {
        if (i >= 0L)
            return BigInteger.valueOf(i);
        else {
            int upper = (int) (i >>> 32);
            int lower = (int) i;

            // return (upper << 32) + lower
            return (BigInteger.valueOf(Integer.toUnsignedLong(upper))).shiftLeft(32).
                add(BigInteger.valueOf(Integer.toUnsignedLong(lower)));
        }
    }

    
Returns a string representation of the long argument as an unsigned integer in base 16. 
The unsigned long value is the argument plus 264 if the argument is negative; otherwise, it is equal to the argument. This value is converted to a string of ASCII digits in hexadecimal (base 16) with no extra leading 0s. 
The value of the argument can be recovered from the returned string s by calling Long.parseUnsignedLong(s,
16). 
If the unsigned magnitude is zero, it is represented by a single zero character '0' ('\u005Cu0030'); otherwise, the first character of the representation of the unsigned magnitude will not be the zero character. The following characters are used as hexadecimal digits: 
 0123456789abcdef 
 These are the characters '\u005Cu0030' through '\u005Cu0039' and '\u005Cu0061' through '\u005Cu0066'. If uppercase letters are desired, the String.toUpperCase() method may be called on the result: 
 Long.toHexString(n).toUpperCase() 
Params:
i –  a long to be converted to a string.
See Also:
parseUnsignedLong(String, int)
toUnsignedString(long, int)
Returns:
 the string representation of the unsigned long value represented by the argument in hexadecimal (base 16).
Since:
  1.0.2/**
     * Returns a string representation of the {@code long}
     * argument as an unsigned integer in base&nbsp;16.
     *
     * <p>The unsigned {@code long} value is the argument plus
     * 2<sup>64</sup> if the argument is negative; otherwise, it is
     * equal to the argument.  This value is converted to a string of
     * ASCII digits in hexadecimal (base&nbsp;16) with no extra
     * leading {@code 0}s.
     *
     * <p>The value of the argument can be recovered from the returned
     * string {@code s} by calling {@link
     * Long#parseUnsignedLong(String, int) Long.parseUnsignedLong(s,
     * 16)}.
     *
     * <p>If the unsigned magnitude is zero, it is represented by a
     * single zero character {@code '0'} ({@code '\u005Cu0030'});
     * otherwise, the first character of the representation of the
     * unsigned magnitude will not be the zero character. The
     * following characters are used as hexadecimal digits:
     *
     * <blockquote>
     *  {@code 0123456789abcdef}
     * </blockquote>
     *
     * These are the characters {@code '\u005Cu0030'} through
     * {@code '\u005Cu0039'} and  {@code '\u005Cu0061'} through
     * {@code '\u005Cu0066'}.  If uppercase letters are desired,
     * the {@link java.lang.String#toUpperCase()} method may be called
     * on the result:
     *
     * <blockquote>
     *  {@code Long.toHexString(n).toUpperCase()}
     * </blockquote>
     *
     * @param   i   a {@code long} to be converted to a string.
     * @return  the string representation of the unsigned {@code long}
     *          value represented by the argument in hexadecimal
     *          (base&nbsp;16).
     * @see #parseUnsignedLong(String, int)
     * @see #toUnsignedString(long, int)
     * @since   1.0.2
     */
    public static String toHexString(long i) {
        return toUnsignedString0(i, 4);
    }

    
Returns a string representation of the long argument as an unsigned integer in base 8. 
The unsigned long value is the argument plus 264 if the argument is negative; otherwise, it is equal to the argument. This value is converted to a string of ASCII digits in octal (base 8) with no extra leading 0s. 
The value of the argument can be recovered from the returned string s by calling Long.parseUnsignedLong(s,
8). 
If the unsigned magnitude is zero, it is represented by a single zero character '0' ('\u005Cu0030'); otherwise, the first character of the representation of the unsigned magnitude will not be the zero character. The following characters are used as octal digits: 
 01234567 
 These are the characters '\u005Cu0030' through '\u005Cu0037'. 
Params:
i –  a long to be converted to a string.
See Also:
parseUnsignedLong(String, int)
toUnsignedString(long, int)
Returns:
 the string representation of the unsigned long value represented by the argument in octal (base 8).
Since:
  1.0.2/**
     * Returns a string representation of the {@code long}
     * argument as an unsigned integer in base&nbsp;8.
     *
     * <p>The unsigned {@code long} value is the argument plus
     * 2<sup>64</sup> if the argument is negative; otherwise, it is
     * equal to the argument.  This value is converted to a string of
     * ASCII digits in octal (base&nbsp;8) with no extra leading
     * {@code 0}s.
     *
     * <p>The value of the argument can be recovered from the returned
     * string {@code s} by calling {@link
     * Long#parseUnsignedLong(String, int) Long.parseUnsignedLong(s,
     * 8)}.
     *
     * <p>If the unsigned magnitude is zero, it is represented by a
     * single zero character {@code '0'} ({@code '\u005Cu0030'});
     * otherwise, the first character of the representation of the
     * unsigned magnitude will not be the zero character. The
     * following characters are used as octal digits:
     *
     * <blockquote>
     *  {@code 01234567}
     * </blockquote>
     *
     * These are the characters {@code '\u005Cu0030'} through
     * {@code '\u005Cu0037'}.
     *
     * @param   i   a {@code long} to be converted to a string.
     * @return  the string representation of the unsigned {@code long}
     *          value represented by the argument in octal (base&nbsp;8).
     * @see #parseUnsignedLong(String, int)
     * @see #toUnsignedString(long, int)
     * @since   1.0.2
     */
    public static String toOctalString(long i) {
        return toUnsignedString0(i, 3);
    }

    
Returns a string representation of the long argument as an unsigned integer in base 2. 
The unsigned long value is the argument plus 264 if the argument is negative; otherwise, it is equal to the argument. This value is converted to a string of ASCII digits in binary (base 2) with no extra leading 0s. 
The value of the argument can be recovered from the returned string s by calling Long.parseUnsignedLong(s,
2). 
If the unsigned magnitude is zero, it is represented by a single zero character '0' ('\u005Cu0030'); otherwise, the first character of the representation of the unsigned magnitude will not be the zero character. The characters '0' ('\u005Cu0030') and 
'1' ('\u005Cu0031') are used as binary digits. 
Params:
i –  a long to be converted to a string.
See Also:
parseUnsignedLong(String, int)
toUnsignedString(long, int)
Returns:
 the string representation of the unsigned long value represented by the argument in binary (base 2).
Since:
  1.0.2/**
     * Returns a string representation of the {@code long}
     * argument as an unsigned integer in base&nbsp;2.
     *
     * <p>The unsigned {@code long} value is the argument plus
     * 2<sup>64</sup> if the argument is negative; otherwise, it is
     * equal to the argument.  This value is converted to a string of
     * ASCII digits in binary (base&nbsp;2) with no extra leading
     * {@code 0}s.
     *
     * <p>The value of the argument can be recovered from the returned
     * string {@code s} by calling {@link
     * Long#parseUnsignedLong(String, int) Long.parseUnsignedLong(s,
     * 2)}.
     *
     * <p>If the unsigned magnitude is zero, it is represented by a
     * single zero character {@code '0'} ({@code '\u005Cu0030'});
     * otherwise, the first character of the representation of the
     * unsigned magnitude will not be the zero character. The
     * characters {@code '0'} ({@code '\u005Cu0030'}) and {@code
     * '1'} ({@code '\u005Cu0031'}) are used as binary digits.
     *
     * @param   i   a {@code long} to be converted to a string.
     * @return  the string representation of the unsigned {@code long}
     *          value represented by the argument in binary (base&nbsp;2).
     * @see #parseUnsignedLong(String, int)
     * @see #toUnsignedString(long, int)
     * @since   1.0.2
     */
    public static String toBinaryString(long i) {
        return toUnsignedString0(i, 1);
    }

    
Format a long (treated as unsigned) into a String.
Params:
val – the value to format
shift – the log2 of the base to format in (4 for hex, 3 for octal, 1 for binary)/**
     * Format a long (treated as unsigned) into a String.
     * @param val the value to format
     * @param shift the log2 of the base to format in (4 for hex, 3 for octal, 1 for binary)
     */
    static String toUnsignedString0(long val, int shift) {
        // assert shift > 0 && shift <=5 : "Illegal shift value";
        int mag = Long.SIZE - Long.numberOfLeadingZeros(val);
        int chars = Math.max(((mag + (shift - 1)) / shift), 1);
        if (COMPACT_STRINGS) {
            byte[] buf = new byte[chars];
            formatUnsignedLong0(val, shift, buf, 0, chars);
            return new String(buf, LATIN1);
        } else {
            byte[] buf = new byte[chars * 2];
            formatUnsignedLong0UTF16(val, shift, buf, 0, chars);
            return new String(buf, UTF16);
        }
    }

    /**
     * Format a long (treated as unsigned) into a character buffer. If
     * {@code len} exceeds the formatted ASCII representation of {@code val},
     * {@code buf} will be padded with leading zeroes.
     *
     * @param val the unsigned long to format
     * @param shift the log2 of the base to format in (4 for hex, 3 for octal, 1 for binary)
     * @param buf the character buffer to write to
     * @param offset the offset in the destination buffer to start at
     * @param len the number of characters to write
     */

    
byte[]/LATIN1 version    /** byte[]/LATIN1 version    */
    static void formatUnsignedLong0(long val, int shift, byte[] buf, int offset, int len) {
        int charPos = offset + len;
        int radix = 1 << shift;
        int mask = radix - 1;
        do {
            buf[--charPos] = (byte)Integer.digits[((int) val) & mask];
            val >>>= shift;
        } while (charPos > offset);
    }

    
byte[]/UTF16 version    /** byte[]/UTF16 version    */
    private static void formatUnsignedLong0UTF16(long val, int shift, byte[] buf, int offset, int len) {
        int charPos = offset + len;
        int radix = 1 << shift;
        int mask = radix - 1;
        do {
            StringUTF16.putChar(buf, --charPos, Integer.digits[((int) val) & mask]);
            val >>>= shift;
        } while (charPos > offset);
    }

    static String fastUUID(long lsb, long msb) {
        if (COMPACT_STRINGS) {
            byte[] buf = new byte[36];
            formatUnsignedLong0(lsb,        4, buf, 24, 12);
            formatUnsignedLong0(lsb >>> 48, 4, buf, 19, 4);
            formatUnsignedLong0(msb,        4, buf, 14, 4);
            formatUnsignedLong0(msb >>> 16, 4, buf, 9,  4);
            formatUnsignedLong0(msb >>> 32, 4, buf, 0,  8);

            buf[23] = '-';
            buf[18] = '-';
            buf[13] = '-';
            buf[8]  = '-';

            return new String(buf, LATIN1);
        } else {
            byte[] buf = new byte[72];

            formatUnsignedLong0UTF16(lsb,        4, buf, 24, 12);
            formatUnsignedLong0UTF16(lsb >>> 48, 4, buf, 19, 4);
            formatUnsignedLong0UTF16(msb,        4, buf, 14, 4);
            formatUnsignedLong0UTF16(msb >>> 16, 4, buf, 9,  4);
            formatUnsignedLong0UTF16(msb >>> 32, 4, buf, 0,  8);

            StringUTF16.putChar(buf, 23, '-');
            StringUTF16.putChar(buf, 18, '-');
            StringUTF16.putChar(buf, 13, '-');
            StringUTF16.putChar(buf,  8, '-');

            return new String(buf, UTF16);
        }
    }

    
Returns a String object representing the specified long. The argument is converted to signed decimal representation and returned as a string, exactly as if the argument and the radix 10 were given as arguments to the toString(long, int) method. 
Params:
i –  a long to be converted.
Returns:
 a string representation of the argument in base 10./**
     * Returns a {@code String} object representing the specified
     * {@code long}.  The argument is converted to signed decimal
     * representation and returned as a string, exactly as if the
     * argument and the radix 10 were given as arguments to the {@link
     * #toString(long, int)} method.
     *
     * @param   i   a {@code long} to be converted.
     * @return  a string representation of the argument in base&nbsp;10.
     */
    public static String toString(long i) {
        int size = stringSize(i);
        if (COMPACT_STRINGS) {
            byte[] buf = new byte[size];
            getChars(i, size, buf);
            return new String(buf, LATIN1);
        } else {
            byte[] buf = new byte[size * 2];
            StringUTF16.getChars(i, size, buf);
            return new String(buf, UTF16);
        }
    }

    
Returns a string representation of the argument as an unsigned decimal value. The argument is converted to unsigned decimal representation and returned as a string exactly as if the argument and radix 10 were given as arguments to the toUnsignedString(long, int) method. 
Params:
i –  an integer to be converted to an unsigned string.
See Also:
toUnsignedString(long, int)
Returns:
 an unsigned string representation of the argument.
Since:
1.8/**
     * Returns a string representation of the argument as an unsigned
     * decimal value.
     *
     * The argument is converted to unsigned decimal representation
     * and returned as a string exactly as if the argument and radix
     * 10 were given as arguments to the {@link #toUnsignedString(long,
     * int)} method.
     *
     * @param   i  an integer to be converted to an unsigned string.
     * @return  an unsigned string representation of the argument.
     * @see     #toUnsignedString(long, int)
     * @since 1.8
     */
    public static String toUnsignedString(long i) {
        return toUnsignedString(i, 10);
    }

    
Places characters representing the long i into the
character array buf. The characters are placed into
the buffer backwards starting with the least significant
digit at the specified index (exclusive), and working
backwards from there.
Params:
i –     value to convert
index – next index, after the least significant digit
buf –   target buffer, Latin1-encoded
Implementation Note:
This method converts positive inputs into negative
values, to cover the Long.MIN_VALUE case. Converting otherwise
(negative to positive) will expose -Long.MIN_VALUE that overflows
long.
Returns:
index of the most significant digit or minus sign, if present/**
     * Places characters representing the long i into the
     * character array buf. The characters are placed into
     * the buffer backwards starting with the least significant
     * digit at the specified index (exclusive), and working
     * backwards from there.
     *
     * @implNote This method converts positive inputs into negative
     * values, to cover the Long.MIN_VALUE case. Converting otherwise
     * (negative to positive) will expose -Long.MIN_VALUE that overflows
     * long.
     *
     * @param i     value to convert
     * @param index next index, after the least significant digit
     * @param buf   target buffer, Latin1-encoded
     * @return index of the most significant digit or minus sign, if present
     */
    static int getChars(long i, int index, byte[] buf) {
        long q;
        int r;
        int charPos = index;

        boolean negative = (i < 0);
        if (!negative) {
            i = -i;
        }

        // Get 2 digits/iteration using longs until quotient fits into an int
        while (i <= Integer.MIN_VALUE) {
            q = i / 100;
            r = (int)((q * 100) - i);
            i = q;
            buf[--charPos] = Integer.DigitOnes[r];
            buf[--charPos] = Integer.DigitTens[r];
        }

        // Get 2 digits/iteration using ints
        int q2;
        int i2 = (int)i;
        while (i2 <= -100) {
            q2 = i2 / 100;
            r  = (q2 * 100) - i2;
            i2 = q2;
            buf[--charPos] = Integer.DigitOnes[r];
            buf[--charPos] = Integer.DigitTens[r];
        }

        // We know there are at most two digits left at this point.
        q2 = i2 / 10;
        r  = (q2 * 10) - i2;
        buf[--charPos] = (byte)('0' + r);

        // Whatever left is the remaining digit.
        if (q2 < 0) {
            buf[--charPos] = (byte)('0' - q2);
        }

        if (negative) {
            buf[--charPos] = (byte)'-';
        }
        return charPos;
    }

    
Returns the string representation size for a given long value.
Params:
x – long value
Returns:
string size
Implementation Note:
There are other ways to compute this: e.g. binary search,
but values are biased heavily towards zero, and therefore linear search
wins. The iteration results are also routinely inlined in the generated
code after loop unrolling./**
     * Returns the string representation size for a given long value.
     *
     * @param x long value
     * @return string size
     *
     * @implNote There are other ways to compute this: e.g. binary search,
     * but values are biased heavily towards zero, and therefore linear search
     * wins. The iteration results are also routinely inlined in the generated
     * code after loop unrolling.
     */
    static int stringSize(long x) {
        int d = 1;
        if (x >= 0) {
            d = 0;
            x = -x;
        }
        long p = -10;
        for (int i = 1; i < 19; i++) {
            if (x > p)
                return i + d;
            p = 10 * p;
        }
        return 19 + d;
    }

    
Parses the string argument as a signed long in the radix specified by the second argument. The characters in the string must all be digits of the specified radix (as determined by whether Character.digit(char, int) returns a nonnegative value), except that the first character may be an ASCII minus sign '-' ('\u005Cu002D') to indicate a negative value or an ASCII plus sign '+' ('\u005Cu002B') to indicate a positive value. The resulting long value is returned. 
Note that neither the character L ('\u005Cu004C') nor l ('\u005Cu006C') is permitted to appear at the end of the string as a type indicator, as would be permitted in Java programming language source code - except that either L or l may appear as a digit for a radix greater than or equal to 22. 
An exception of type NumberFormatException is thrown if any of the following situations occurs: 

The first argument is null or is a string of length zero. 
The radix is either smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX. 
Any character of the string is not a digit of the specified radix, except that the first character may be a minus sign '-' ('\u005Cu002d') or plus sign 
'+' ('\u005Cu002B') provided that the string is longer than length 1. 
The value represented by the string is not a value of type long. 
Examples:
parseLong("0", 10) returns 0L
parseLong("473", 10) returns 473L
parseLong("+42", 10) returns 42L
parseLong("-0", 10) returns 0L
parseLong("-FF", 16) returns -255L
parseLong("1100110", 2) returns 102L
parseLong("99", 8) throws a NumberFormatException
parseLong("Hazelnut", 10) throws a NumberFormatException
parseLong("Hazelnut", 36) returns 1356099454469L

Params:
s –  the String containing the long representation to be parsed.
radix –  the radix to be used while parsing s.
Throws:
NumberFormatException –  if the string does not contain a parsable long.
Returns:
 the long represented by the string argument in the specified radix./**
     * Parses the string argument as a signed {@code long} in the
     * radix specified by the second argument. The characters in the
     * string must all be digits of the specified radix (as determined
     * by whether {@link java.lang.Character#digit(char, int)} returns
     * a nonnegative value), except that the first character may be an
     * ASCII minus sign {@code '-'} ({@code '\u005Cu002D'}) to
     * indicate a negative value or an ASCII plus sign {@code '+'}
     * ({@code '\u005Cu002B'}) to indicate a positive value. The
     * resulting {@code long} value is returned.
     *
     * <p>Note that neither the character {@code L}
     * ({@code '\u005Cu004C'}) nor {@code l}
     * ({@code '\u005Cu006C'}) is permitted to appear at the end
     * of the string as a type indicator, as would be permitted in
     * Java programming language source code - except that either
     * {@code L} or {@code l} may appear as a digit for a
     * radix greater than or equal to 22.
     *
     * <p>An exception of type {@code NumberFormatException} is
     * thrown if any of the following situations occurs:
     * <ul>
     *
     * <li>The first argument is {@code null} or is a string of
     * length zero.
     *
     * <li>The {@code radix} is either smaller than {@link
     * java.lang.Character#MIN_RADIX} or larger than {@link
     * java.lang.Character#MAX_RADIX}.
     *
     * <li>Any character of the string is not a digit of the specified
     * radix, except that the first character may be a minus sign
     * {@code '-'} ({@code '\u005Cu002d'}) or plus sign {@code
     * '+'} ({@code '\u005Cu002B'}) provided that the string is
     * longer than length 1.
     *
     * <li>The value represented by the string is not a value of type
     *      {@code long}.
     * </ul>
     *
     * <p>Examples:
     * <blockquote><pre>
     * parseLong("0", 10) returns 0L
     * parseLong("473", 10) returns 473L
     * parseLong("+42", 10) returns 42L
     * parseLong("-0", 10) returns 0L
     * parseLong("-FF", 16) returns -255L
     * parseLong("1100110", 2) returns 102L
     * parseLong("99", 8) throws a NumberFormatException
     * parseLong("Hazelnut", 10) throws a NumberFormatException
     * parseLong("Hazelnut", 36) returns 1356099454469L
     * </pre></blockquote>
     *
     * @param      s       the {@code String} containing the
     *                     {@code long} representation to be parsed.
     * @param      radix   the radix to be used while parsing {@code s}.
     * @return     the {@code long} represented by the string argument in
     *             the specified radix.
     * @throws     NumberFormatException  if the string does not contain a
     *             parsable {@code long}.
     */
    public static long parseLong(String s, int radix)
              throws NumberFormatException
    {
        if (s == null) {
            throw new NumberFormatException("null");
        }

        if (radix < Character.MIN_RADIX) {
            throw new NumberFormatException("radix " + radix +
                                            " less than Character.MIN_RADIX");
        }
        if (radix > Character.MAX_RADIX) {
            throw new NumberFormatException("radix " + radix +
                                            " greater than Character.MAX_RADIX");
        }

        boolean negative = false;
        int i = 0, len = s.length();
        long limit = -Long.MAX_VALUE;

        if (len > 0) {
            char firstChar = s.charAt(0);
            if (firstChar < '0') { // Possible leading "+" or "-"
                if (firstChar == '-') {
                    negative = true;
                    limit = Long.MIN_VALUE;
                } else if (firstChar != '+') {
                    throw NumberFormatException.forInputString(s);
                }

                if (len == 1) { // Cannot have lone "+" or "-"
                    throw NumberFormatException.forInputString(s);
                }
                i++;
            }
            long multmin = limit / radix;
            long result = 0;
            while (i < len) {
                // Accumulating negatively avoids surprises near MAX_VALUE
                int digit = Character.digit(s.charAt(i++),radix);
                if (digit < 0 || result < multmin) {
                    throw NumberFormatException.forInputString(s);
                }
                result *= radix;
                if (result < limit + digit) {
                    throw NumberFormatException.forInputString(s);
                }
                result -= digit;
            }
            return negative ? result : -result;
        } else {
            throw NumberFormatException.forInputString(s);
        }
    }

    
Parses the CharSequence argument as a signed long in the specified radix, beginning at the specified beginIndex and extending to endIndex - 1. 
The method does not take steps to guard against the CharSequence being mutated while parsing. 
Params:
s –  the CharSequence containing the long representation to be parsed
beginIndex –   the beginning index, inclusive.
endIndex –     the ending index, exclusive.
radix –  the radix to be used while parsing s.
Throws:
NullPointerException –  if s is null.
IndexOutOfBoundsException –  if beginIndex is negative, or if beginIndex is greater than endIndex or if endIndex is greater than s.length().
NumberFormatException –  if the CharSequence does not contain a parsable int in the specified radix, or if radix is either smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX.
Returns:
 the signed long represented by the subsequence in the specified radix.
Since:
 9/**
     * Parses the {@link CharSequence} argument as a signed {@code long} in
     * the specified {@code radix}, beginning at the specified
     * {@code beginIndex} and extending to {@code endIndex - 1}.
     *
     * <p>The method does not take steps to guard against the
     * {@code CharSequence} being mutated while parsing.
     *
     * @param      s   the {@code CharSequence} containing the {@code long}
     *                  representation to be parsed
     * @param      beginIndex   the beginning index, inclusive.
     * @param      endIndex     the ending index, exclusive.
     * @param      radix   the radix to be used while parsing {@code s}.
     * @return     the signed {@code long} represented by the subsequence in
     *             the specified radix.
     * @throws     NullPointerException  if {@code s} is null.
     * @throws     IndexOutOfBoundsException  if {@code beginIndex} is
     *             negative, or if {@code beginIndex} is greater than
     *             {@code endIndex} or if {@code endIndex} is greater than
     *             {@code s.length()}.
     * @throws     NumberFormatException  if the {@code CharSequence} does not
     *             contain a parsable {@code int} in the specified
     *             {@code radix}, or if {@code radix} is either smaller than
     *             {@link java.lang.Character#MIN_RADIX} or larger than
     *             {@link java.lang.Character#MAX_RADIX}.
     * @since  9
     */
    public static long parseLong(CharSequence s, int beginIndex, int endIndex, int radix)
                throws NumberFormatException {
        s = Objects.requireNonNull(s);

        if (beginIndex < 0 || beginIndex > endIndex || endIndex > s.length()) {
            throw new IndexOutOfBoundsException();
        }
        if (radix < Character.MIN_RADIX) {
            throw new NumberFormatException("radix " + radix +
                    " less than Character.MIN_RADIX");
        }
        if (radix > Character.MAX_RADIX) {
            throw new NumberFormatException("radix " + radix +
                    " greater than Character.MAX_RADIX");
        }

        boolean negative = false;
        int i = beginIndex;
        long limit = -Long.MAX_VALUE;

        if (i < endIndex) {
            char firstChar = s.charAt(i);
            if (firstChar < '0') { // Possible leading "+" or "-"
                if (firstChar == '-') {
                    negative = true;
                    limit = Long.MIN_VALUE;
                } else if (firstChar != '+') {
                    throw NumberFormatException.forCharSequence(s, beginIndex,
                            endIndex, i);
                }
                i++;
            }
            if (i >= endIndex) { // Cannot have lone "+", "-" or ""
                throw NumberFormatException.forCharSequence(s, beginIndex,
                        endIndex, i);
            }
            long multmin = limit / radix;
            long result = 0;
            while (i < endIndex) {
                // Accumulating negatively avoids surprises near MAX_VALUE
                int digit = Character.digit(s.charAt(i), radix);
                if (digit < 0 || result < multmin) {
                    throw NumberFormatException.forCharSequence(s, beginIndex,
                            endIndex, i);
                }
                result *= radix;
                if (result < limit + digit) {
                    throw NumberFormatException.forCharSequence(s, beginIndex,
                            endIndex, i);
                }
                i++;
                result -= digit;
            }
            return negative ? result : -result;
        } else {
            throw new NumberFormatException("");
        }
    }

    
Parses the string argument as a signed decimal long. The characters in the string must all be decimal digits, except that the first character may be an ASCII minus sign '-' (\u005Cu002D') to indicate a negative value or an ASCII plus sign '+' ('\u005Cu002B') to indicate a positive value. The resulting long value is returned, exactly as if the argument and the radix 10 were given as arguments to the parseLong(String, int) method. 
Note that neither the character L ('\u005Cu004C') nor l ('\u005Cu006C') is permitted to appear at the end of the string as a type indicator, as would be permitted in Java programming language source code. 
Params:
s –  a String containing the long representation to be parsed
Throws:
NumberFormatException –  if the string does not contain a parsable long.
Returns:
 the long represented by the argument in decimal./**
     * Parses the string argument as a signed decimal {@code long}.
     * The characters in the string must all be decimal digits, except
     * that the first character may be an ASCII minus sign {@code '-'}
     * ({@code \u005Cu002D'}) to indicate a negative value or an
     * ASCII plus sign {@code '+'} ({@code '\u005Cu002B'}) to
     * indicate a positive value. The resulting {@code long} value is
     * returned, exactly as if the argument and the radix {@code 10}
     * were given as arguments to the {@link
     * #parseLong(java.lang.String, int)} method.
     *
     * <p>Note that neither the character {@code L}
     * ({@code '\u005Cu004C'}) nor {@code l}
     * ({@code '\u005Cu006C'}) is permitted to appear at the end
     * of the string as a type indicator, as would be permitted in
     * Java programming language source code.
     *
     * @param      s   a {@code String} containing the {@code long}
     *             representation to be parsed
     * @return     the {@code long} represented by the argument in
     *             decimal.
     * @throws     NumberFormatException  if the string does not contain a
     *             parsable {@code long}.
     */
    public static long parseLong(String s) throws NumberFormatException {
        return parseLong(s, 10);
    }

    
Parses the string argument as an unsigned long in the radix specified by the second argument. An unsigned integer maps the values usually associated with negative numbers to positive numbers larger than MAX_VALUE. The characters in the string must all be digits of the specified radix (as determined by whether Character.digit(char, int) returns a nonnegative value), except that the first character may be an ASCII plus sign '+' ('\u005Cu002B'). The resulting integer value is returned. 
An exception of type NumberFormatException is thrown if any of the following situations occurs: 

The first argument is null or is a string of length zero. 
The radix is either smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX. 
Any character of the string is not a digit of the specified radix, except that the first character may be a plus sign '+' ('\u005Cu002B') provided that the string is longer than length 1. 
The value represented by the string is larger than the largest unsigned long, 264-1.

Params:
s –  the String containing the unsigned integer representation to be parsed
radix –  the radix to be used while parsing s.
Throws:
NumberFormatException – if the String does not contain a parsable long.
Returns:
 the unsigned long represented by the string argument in the specified radix.
Since:
1.8/**
     * Parses the string argument as an unsigned {@code long} in the
     * radix specified by the second argument.  An unsigned integer
     * maps the values usually associated with negative numbers to
     * positive numbers larger than {@code MAX_VALUE}.
     *
     * The characters in the string must all be digits of the
     * specified radix (as determined by whether {@link
     * java.lang.Character#digit(char, int)} returns a nonnegative
     * value), except that the first character may be an ASCII plus
     * sign {@code '+'} ({@code '\u005Cu002B'}). The resulting
     * integer value is returned.
     *
     * <p>An exception of type {@code NumberFormatException} is
     * thrown if any of the following situations occurs:
     * <ul>
     * <li>The first argument is {@code null} or is a string of
     * length zero.
     *
     * <li>The radix is either smaller than
     * {@link java.lang.Character#MIN_RADIX} or
     * larger than {@link java.lang.Character#MAX_RADIX}.
     *
     * <li>Any character of the string is not a digit of the specified
     * radix, except that the first character may be a plus sign
     * {@code '+'} ({@code '\u005Cu002B'}) provided that the
     * string is longer than length 1.
     *
     * <li>The value represented by the string is larger than the
     * largest unsigned {@code long}, 2<sup>64</sup>-1.
     *
     * </ul>
     *
     *
     * @param      s   the {@code String} containing the unsigned integer
     *                  representation to be parsed
     * @param      radix   the radix to be used while parsing {@code s}.
     * @return     the unsigned {@code long} represented by the string
     *             argument in the specified radix.
     * @throws     NumberFormatException if the {@code String}
     *             does not contain a parsable {@code long}.
     * @since 1.8
     */
    public static long parseUnsignedLong(String s, int radix)
                throws NumberFormatException {
        if (s == null)  {
            throw new NumberFormatException("null");
        }

        int len = s.length();
        if (len > 0) {
            char firstChar = s.charAt(0);
            if (firstChar == '-') {
                throw new
                    NumberFormatException(String.format("Illegal leading minus sign " +
                                                       "on unsigned string %s.", s));
            } else {
                if (len <= 12 || // Long.MAX_VALUE in Character.MAX_RADIX is 13 digits
                    (radix == 10 && len <= 18) ) { // Long.MAX_VALUE in base 10 is 19 digits
                    return parseLong(s, radix);
                }

                // No need for range checks on len due to testing above.
                long first = parseLong(s, 0, len - 1, radix);
                int second = Character.digit(s.charAt(len - 1), radix);
                if (second < 0) {
                    throw new NumberFormatException("Bad digit at end of " + s);
                }
                long result = first * radix + second;

                /*
                 * Test leftmost bits of multiprecision extension of first*radix
                 * for overflow. The number of bits needed is defined by
                 * GUARD_BIT = ceil(log2(Character.MAX_RADIX)) + 1 = 7. Then
                 * int guard = radix*(int)(first >>> (64 - GUARD_BIT)) and
                 * overflow is tested by splitting guard in the ranges
                 * guard < 92, 92 <= guard < 128, and 128 <= guard, where
                 * 92 = 128 - Character.MAX_RADIX. Note that guard cannot take
                 * on a value which does not include a prime factor in the legal
                 * radix range.
                 */
                int guard = radix * (int) (first >>> 57);
                if (guard >= 128 ||
                    (result >= 0 && guard >= 128 - Character.MAX_RADIX)) {
                    /*
                     * For purposes of exposition, the programmatic statements
                     * below should be taken to be multi-precision, i.e., not
                     * subject to overflow.
                     *
                     * A) Condition guard >= 128:
                     * If guard >= 128 then first*radix >= 2^7 * 2^57 = 2^64
                     * hence always overflow.
                     *
                     * B) Condition guard < 92:
                     * Define left7 = first >>> 57.
                     * Given first = (left7 * 2^57) + (first & (2^57 - 1)) then
                     * result <= (radix*left7)*2^57 + radix*(2^57 - 1) + second.
                     * Thus if radix*left7 < 92, radix <= 36, and second < 36,
                     * then result < 92*2^57 + 36*(2^57 - 1) + 36 = 2^64 hence
                     * never overflow.
                     *
                     * C) Condition 92 <= guard < 128:
                     * first*radix + second >= radix*left7*2^57 + second
                     * so that first*radix + second >= 92*2^57 + 0 > 2^63
                     *
                     * D) Condition guard < 128:
                     * radix*first <= (radix*left7) * 2^57 + radix*(2^57 - 1)
                     * so
                     * radix*first + second <= (radix*left7) * 2^57 + radix*(2^57 - 1) + 36
                     * thus
                     * radix*first + second < 128 * 2^57 + 36*2^57 - radix + 36
                     * whence
                     * radix*first + second < 2^64 + 2^6*2^57 = 2^64 + 2^63
                     *
                     * E) Conditions C, D, and result >= 0:
                     * C and D combined imply the mathematical result
                     * 2^63 < first*radix + second < 2^64 + 2^63. The lower
                     * bound is therefore negative as a signed long, but the
                     * upper bound is too small to overflow again after the
                     * signed long overflows to positive above 2^64 - 1. Hence
                     * result >= 0 implies overflow given C and D.
                     */
                    throw new NumberFormatException(String.format("String value %s exceeds " +
                                                                  "range of unsigned long.", s));
                }
                return result;
            }
        } else {
            throw NumberFormatException.forInputString(s);
        }
    }

    
Parses the CharSequence argument as an unsigned long in the specified radix, beginning at the specified beginIndex and extending to endIndex - 1. 
The method does not take steps to guard against the CharSequence being mutated while parsing. 
Params:
s –  the CharSequence containing the unsigned long representation to be parsed
beginIndex –   the beginning index, inclusive.
endIndex –     the ending index, exclusive.
radix –  the radix to be used while parsing s.
Throws:
NullPointerException –  if s is null.
IndexOutOfBoundsException –  if beginIndex is negative, or if beginIndex is greater than endIndex or if endIndex is greater than s.length().
NumberFormatException –  if the CharSequence does not contain a parsable unsigned long in the specified radix, or if radix is either smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX.
Returns:
 the unsigned long represented by the subsequence in the specified radix.
Since:
 9/**
     * Parses the {@link CharSequence} argument as an unsigned {@code long} in
     * the specified {@code radix}, beginning at the specified
     * {@code beginIndex} and extending to {@code endIndex - 1}.
     *
     * <p>The method does not take steps to guard against the
     * {@code CharSequence} being mutated while parsing.
     *
     * @param      s   the {@code CharSequence} containing the unsigned
     *                 {@code long} representation to be parsed
     * @param      beginIndex   the beginning index, inclusive.
     * @param      endIndex     the ending index, exclusive.
     * @param      radix   the radix to be used while parsing {@code s}.
     * @return     the unsigned {@code long} represented by the subsequence in
     *             the specified radix.
     * @throws     NullPointerException  if {@code s} is null.
     * @throws     IndexOutOfBoundsException  if {@code beginIndex} is
     *             negative, or if {@code beginIndex} is greater than
     *             {@code endIndex} or if {@code endIndex} is greater than
     *             {@code s.length()}.
     * @throws     NumberFormatException  if the {@code CharSequence} does not
     *             contain a parsable unsigned {@code long} in the specified
     *             {@code radix}, or if {@code radix} is either smaller than
     *             {@link java.lang.Character#MIN_RADIX} or larger than
     *             {@link java.lang.Character#MAX_RADIX}.
     * @since  9
     */
    public static long parseUnsignedLong(CharSequence s, int beginIndex, int endIndex, int radix)
                throws NumberFormatException {
        s = Objects.requireNonNull(s);

        if (beginIndex < 0 || beginIndex > endIndex || endIndex > s.length()) {
            throw new IndexOutOfBoundsException();
        }
        int start = beginIndex, len = endIndex - beginIndex;

        if (len > 0) {
            char firstChar = s.charAt(start);
            if (firstChar == '-') {
                throw new NumberFormatException(String.format("Illegal leading minus sign " +
                        "on unsigned string %s.", s.subSequence(start, start + len)));
            } else {
                if (len <= 12 || // Long.MAX_VALUE in Character.MAX_RADIX is 13 digits
                    (radix == 10 && len <= 18) ) { // Long.MAX_VALUE in base 10 is 19 digits
                    return parseLong(s, start, start + len, radix);
                }

                // No need for range checks on end due to testing above.
                long first = parseLong(s, start, start + len - 1, radix);
                int second = Character.digit(s.charAt(start + len - 1), radix);
                if (second < 0) {
                    throw new NumberFormatException("Bad digit at end of " +
                            s.subSequence(start, start + len));
                }
                long result = first * radix + second;

                /*
                 * Test leftmost bits of multiprecision extension of first*radix
                 * for overflow. The number of bits needed is defined by
                 * GUARD_BIT = ceil(log2(Character.MAX_RADIX)) + 1 = 7. Then
                 * int guard = radix*(int)(first >>> (64 - GUARD_BIT)) and
                 * overflow is tested by splitting guard in the ranges
                 * guard < 92, 92 <= guard < 128, and 128 <= guard, where
                 * 92 = 128 - Character.MAX_RADIX. Note that guard cannot take
                 * on a value which does not include a prime factor in the legal
                 * radix range.
                 */
                int guard = radix * (int) (first >>> 57);
                if (guard >= 128 ||
                        (result >= 0 && guard >= 128 - Character.MAX_RADIX)) {
                    /*
                     * For purposes of exposition, the programmatic statements
                     * below should be taken to be multi-precision, i.e., not
                     * subject to overflow.
                     *
                     * A) Condition guard >= 128:
                     * If guard >= 128 then first*radix >= 2^7 * 2^57 = 2^64
                     * hence always overflow.
                     *
                     * B) Condition guard < 92:
                     * Define left7 = first >>> 57.
                     * Given first = (left7 * 2^57) + (first & (2^57 - 1)) then
                     * result <= (radix*left7)*2^57 + radix*(2^57 - 1) + second.
                     * Thus if radix*left7 < 92, radix <= 36, and second < 36,
                     * then result < 92*2^57 + 36*(2^57 - 1) + 36 = 2^64 hence
                     * never overflow.
                     *
                     * C) Condition 92 <= guard < 128:
                     * first*radix + second >= radix*left7*2^57 + second
                     * so that first*radix + second >= 92*2^57 + 0 > 2^63
                     *
                     * D) Condition guard < 128:
                     * radix*first <= (radix*left7) * 2^57 + radix*(2^57 - 1)
                     * so
                     * radix*first + second <= (radix*left7) * 2^57 + radix*(2^57 - 1) + 36
                     * thus
                     * radix*first + second < 128 * 2^57 + 36*2^57 - radix + 36
                     * whence
                     * radix*first + second < 2^64 + 2^6*2^57 = 2^64 + 2^63
                     *
                     * E) Conditions C, D, and result >= 0:
                     * C and D combined imply the mathematical result
                     * 2^63 < first*radix + second < 2^64 + 2^63. The lower
                     * bound is therefore negative as a signed long, but the
                     * upper bound is too small to overflow again after the
                     * signed long overflows to positive above 2^64 - 1. Hence
                     * result >= 0 implies overflow given C and D.
                     */
                    throw new NumberFormatException(String.format("String value %s exceeds " +
                            "range of unsigned long.", s.subSequence(start, start + len)));
                }
                return result;
            }
        } else {
            throw NumberFormatException.forInputString("");
        }
    }

    
Parses the string argument as an unsigned decimal long. The characters in the string must all be decimal digits, except that the first character may be an ASCII plus sign 
'+' ('\u005Cu002B'). The resulting integer value is returned, exactly as if the argument and the radix 10 were given as arguments to the parseUnsignedLong(String, int) method. 
Params:
s –  a String containing the unsigned long representation to be parsed
Throws:
NumberFormatException –  if the string does not contain a
           parsable unsigned integer.
Returns:
 the unsigned long value represented by the decimal string argument
Since:
1.8/**
     * Parses the string argument as an unsigned decimal {@code long}. The
     * characters in the string must all be decimal digits, except
     * that the first character may be an ASCII plus sign {@code
     * '+'} ({@code '\u005Cu002B'}). The resulting integer value
     * is returned, exactly as if the argument and the radix 10 were
     * given as arguments to the {@link
     * #parseUnsignedLong(java.lang.String, int)} method.
     *
     * @param s   a {@code String} containing the unsigned {@code long}
     *            representation to be parsed
     * @return    the unsigned {@code long} value represented by the decimal string argument
     * @throws    NumberFormatException  if the string does not contain a
     *            parsable unsigned integer.
     * @since 1.8
     */
    public static long parseUnsignedLong(String s) throws NumberFormatException {
        return parseUnsignedLong(s, 10);
    }

    
Returns a Long object holding the value extracted from the specified String when parsed with the radix given by the second argument. The first argument is interpreted as representing a signed long in the radix specified by the second argument, exactly as if the arguments were given to the parseLong(String, int) method. The result is a Long object that represents the long value specified by the string. 
In other words, this method returns a Long object equal to the value of: 
 new Long(Long.parseLong(s, radix)) 
Params:
s –       the string to be parsed
radix –  the radix to be used in interpreting s
Throws:
NumberFormatException –  If the String does not contain a parsable long.
Returns:
 a Long object holding the value represented by the string argument in the specified radix./**
     * Returns a {@code Long} object holding the value
     * extracted from the specified {@code String} when parsed
     * with the radix given by the second argument.  The first
     * argument is interpreted as representing a signed
     * {@code long} in the radix specified by the second
     * argument, exactly as if the arguments were given to the {@link
     * #parseLong(java.lang.String, int)} method. The result is a
     * {@code Long} object that represents the {@code long}
     * value specified by the string.
     *
     * <p>In other words, this method returns a {@code Long} object equal
     * to the value of:
     *
     * <blockquote>
     *  {@code new Long(Long.parseLong(s, radix))}
     * </blockquote>
     *
     * @param      s       the string to be parsed
     * @param      radix   the radix to be used in interpreting {@code s}
     * @return     a {@code Long} object holding the value
     *             represented by the string argument in the specified
     *             radix.
     * @throws     NumberFormatException  If the {@code String} does not
     *             contain a parsable {@code long}.
     */
    public static Long valueOf(String s, int radix) throws NumberFormatException {
        return Long.valueOf(parseLong(s, radix));
    }

    
Returns a Long object holding the value of the specified String. The argument is interpreted as representing a signed decimal long, exactly as if the argument were given to the parseLong(String) method. The result is a Long object that represents the integer value specified by the string. 
In other words, this method returns a Long object equal to the value of: 
 new Long(Long.parseLong(s)) 
Params:
s –   the string to be parsed.
Throws:
NumberFormatException –  If the string cannot be parsed as a long.
Returns:
 a Long object holding the value represented by the string argument./**
     * Returns a {@code Long} object holding the value
     * of the specified {@code String}. The argument is
     * interpreted as representing a signed decimal {@code long},
     * exactly as if the argument were given to the {@link
     * #parseLong(java.lang.String)} method. The result is a
     * {@code Long} object that represents the integer value
     * specified by the string.
     *
     * <p>In other words, this method returns a {@code Long} object
     * equal to the value of:
     *
     * <blockquote>
     *  {@code new Long(Long.parseLong(s))}
     * </blockquote>
     *
     * @param      s   the string to be parsed.
     * @return     a {@code Long} object holding the value
     *             represented by the string argument.
     * @throws     NumberFormatException  If the string cannot be parsed
     *             as a {@code long}.
     */
    public static Long valueOf(String s) throws NumberFormatException
    {
        return Long.valueOf(parseLong(s, 10));
    }

    private static class LongCache {
        private LongCache(){}

        static final Long cache[] = new Long[-(-128) + 127 + 1];

        static {
            for(int i = 0; i < cache.length; i++)
                cache[i] = new Long(i - 128);
        }
    }

    
Returns a Long instance representing the specified long value. If a new Long instance is not required, this method should generally be used in preference to the constructor Long(long), as this method is likely to yield significantly better space and time performance by caching frequently requested values. This method will always cache values in the range -128 to 127, inclusive, and may cache other values outside of this range. 
Params:
l – a long value.
Returns:
a Long instance representing l.
Since:
 1.5/**
     * Returns a {@code Long} instance representing the specified
     * {@code long} value.
     * If a new {@code Long} instance is not required, this method
     * should generally be used in preference to the constructor
     * {@link #Long(long)}, as this method is likely to yield
     * significantly better space and time performance by caching
     * frequently requested values.
     *
     * This method will always cache values in the range -128 to 127,
     * inclusive, and may cache other values outside of this range.
     *
     * @param  l a long value.
     * @return a {@code Long} instance representing {@code l}.
     * @since  1.5
     */
    @HotSpotIntrinsicCandidate
    public static Long valueOf(long l) {
        final int offset = 128;
        if (l >= -128 && l <= 127) { // will cache
            return LongCache.cache[(int)l + offset];
        }
        return new Long(l);
    }

    
Decodes a String into a Long. Accepts decimal, hexadecimal, and octal numbers given by the following grammar: 


DecodableString:
Signopt DecimalNumeral
Signopt 0x HexDigits
Signopt 0X HexDigits
Signopt # HexDigits
Signopt 0 OctalDigits
Sign:
- 
+ 

DecimalNumeral, HexDigits, and OctalDigits
are as defined in section 3.10.1 of
The Java™ Language Specification,
except that underscores are not accepted between digits.
The sequence of characters following an optional sign and/or radix specifier ("0x", "0X", "#", or leading zero) is parsed as by the 
Long.parseLong method with the indicated radix (10, 16, or 8). This sequence of characters must represent a positive value or a NumberFormatException will be thrown. The result is negated if first character of the specified String is the minus sign. No whitespace characters are permitted in the String. 
Params:
nm – the String to decode.
Throws:
NumberFormatException –  if the String does not contain a parsable long.
See Also:
parseLong(String, int)
Returns:
 a Long object holding the long value represented by nm
Since:
1.2/**
     * Decodes a {@code String} into a {@code Long}.
     * Accepts decimal, hexadecimal, and octal numbers given by the
     * following grammar:
     *
     * <blockquote>
     * <dl>
     * <dt><i>DecodableString:</i>
     * <dd><i>Sign<sub>opt</sub> DecimalNumeral</i>
     * <dd><i>Sign<sub>opt</sub></i> {@code 0x} <i>HexDigits</i>
     * <dd><i>Sign<sub>opt</sub></i> {@code 0X} <i>HexDigits</i>
     * <dd><i>Sign<sub>opt</sub></i> {@code #} <i>HexDigits</i>
     * <dd><i>Sign<sub>opt</sub></i> {@code 0} <i>OctalDigits</i>
     *
     * <dt><i>Sign:</i>
     * <dd>{@code -}
     * <dd>{@code +}
     * </dl>
     * </blockquote>
     *
     * <i>DecimalNumeral</i>, <i>HexDigits</i>, and <i>OctalDigits</i>
     * are as defined in section 3.10.1 of
     * <cite>The Java&trade; Language Specification</cite>,
     * except that underscores are not accepted between digits.
     *
     * <p>The sequence of characters following an optional
     * sign and/or radix specifier ("{@code 0x}", "{@code 0X}",
     * "{@code #}", or leading zero) is parsed as by the {@code
     * Long.parseLong} method with the indicated radix (10, 16, or 8).
     * This sequence of characters must represent a positive value or
     * a {@link NumberFormatException} will be thrown.  The result is
     * negated if first character of the specified {@code String} is
     * the minus sign.  No whitespace characters are permitted in the
     * {@code String}.
     *
     * @param     nm the {@code String} to decode.
     * @return    a {@code Long} object holding the {@code long}
     *            value represented by {@code nm}
     * @throws    NumberFormatException  if the {@code String} does not
     *            contain a parsable {@code long}.
     * @see java.lang.Long#parseLong(String, int)
     * @since 1.2
     */
    public static Long decode(String nm) throws NumberFormatException {
        int radix = 10;
        int index = 0;
        boolean negative = false;
        Long result;

        if (nm.isEmpty())
            throw new NumberFormatException("Zero length string");
        char firstChar = nm.charAt(0);
        // Handle sign, if present
        if (firstChar == '-') {
            negative = true;
            index++;
        } else if (firstChar == '+')
            index++;

        // Handle radix specifier, if present
        if (nm.startsWith("0x", index) || nm.startsWith("0X", index)) {
            index += 2;
            radix = 16;
        }
        else if (nm.startsWith("#", index)) {
            index ++;
            radix = 16;
        }
        else if (nm.startsWith("0", index) && nm.length() > 1 + index) {
            index ++;
            radix = 8;
        }

        if (nm.startsWith("-", index) || nm.startsWith("+", index))
            throw new NumberFormatException("Sign character in wrong position");

        try {
            result = Long.valueOf(nm.substring(index), radix);
            result = negative ? Long.valueOf(-result.longValue()) : result;
        } catch (NumberFormatException e) {
            // If number is Long.MIN_VALUE, we'll end up here. The next line
            // handles this case, and causes any genuine format error to be
            // rethrown.
            String constant = negative ? ("-" + nm.substring(index))
                                       : nm.substring(index);
            result = Long.valueOf(constant, radix);
        }
        return result;
    }

    
The value of the Long. 
@serial
/**
     * The value of the {@code Long}.
     *
     * @serial
     */
    private final long value;

    
Constructs a newly allocated Long object that represents the specified long argument. 
Params:
value –  the value to be represented by the Long object.
Deprecated:
 It is rarely appropriate to use this constructor. The static factory valueOf(long) is generally a better choice, as it is likely to yield significantly better space and time performance./**
     * Constructs a newly allocated {@code Long} object that
     * represents the specified {@code long} argument.
     *
     * @param   value   the value to be represented by the
     *          {@code Long} object.
     *
     * @deprecated
     * It is rarely appropriate to use this constructor. The static factory
     * {@link #valueOf(long)} is generally a better choice, as it is
     * likely to yield significantly better space and time performance.
     */
    @Deprecated(since="9")
    public Long(long value) {
        this.value = value;
    }

    
Constructs a newly allocated Long object that represents the long value indicated by the String parameter. The string is converted to a long value in exactly the manner used by the parseLong method for radix 10. 
Params:
s –  the String to be converted to a Long.
Throws:
NumberFormatException –  if the String does not contain a parsable long.
Deprecated:
 It is rarely appropriate to use this constructor. Use parseLong(String) to convert a string to a long primitive, or use valueOf(String) to convert a string to a Long object./**
     * Constructs a newly allocated {@code Long} object that
     * represents the {@code long} value indicated by the
     * {@code String} parameter. The string is converted to a
     * {@code long} value in exactly the manner used by the
     * {@code parseLong} method for radix 10.
     *
     * @param      s   the {@code String} to be converted to a
     *             {@code Long}.
     * @throws     NumberFormatException  if the {@code String} does not
     *             contain a parsable {@code long}.
     *
     * @deprecated
     * It is rarely appropriate to use this constructor.
     * Use {@link #parseLong(String)} to convert a string to a
     * {@code long} primitive, or use {@link #valueOf(String)}
     * to convert a string to a {@code Long} object.
     */
    @Deprecated(since="9")
    public Long(String s) throws NumberFormatException {
        this.value = parseLong(s, 10);
    }

    
Returns the value of this Long as a byte after a narrowing primitive conversion. 
@jls
5.1.3 Narrowing Primitive Conversions/**
     * Returns the value of this {@code Long} as a {@code byte} after
     * a narrowing primitive conversion.
     * @jls 5.1.3 Narrowing Primitive Conversions
     */
    public byte byteValue() {
        return (byte)value;
    }

    
Returns the value of this Long as a short after a narrowing primitive conversion. 
@jls
5.1.3 Narrowing Primitive Conversions/**
     * Returns the value of this {@code Long} as a {@code short} after
     * a narrowing primitive conversion.
     * @jls 5.1.3 Narrowing Primitive Conversions
     */
    public short shortValue() {
        return (short)value;
    }

    
Returns the value of this Long as an int after a narrowing primitive conversion. 
@jls
5.1.3 Narrowing Primitive Conversions/**
     * Returns the value of this {@code Long} as an {@code int} after
     * a narrowing primitive conversion.
     * @jls 5.1.3 Narrowing Primitive Conversions
     */
    public int intValue() {
        return (int)value;
    }

    
Returns the value of this Long as a long value. /**
     * Returns the value of this {@code Long} as a
     * {@code long} value.
     */
    @HotSpotIntrinsicCandidate
    public long longValue() {
        return value;
    }

    
Returns the value of this Long as a float after a widening primitive conversion. 
@jls
5.1.2 Widening Primitive Conversions/**
     * Returns the value of this {@code Long} as a {@code float} after
     * a widening primitive conversion.
     * @jls 5.1.2 Widening Primitive Conversions
     */
    public float floatValue() {
        return (float)value;
    }

    
Returns the value of this Long as a double after a widening primitive conversion. 
@jls
5.1.2 Widening Primitive Conversions/**
     * Returns the value of this {@code Long} as a {@code double}
     * after a widening primitive conversion.
     * @jls 5.1.2 Widening Primitive Conversions
     */
    public double doubleValue() {
        return (double)value;
    }

    
Returns a String object representing this Long's value. The value is converted to signed decimal representation and returned as a string, exactly as if the long value were given as an argument to the toString(long) method. 
Returns:
 a string representation of the value of this object in
         base 10./**
     * Returns a {@code String} object representing this
     * {@code Long}'s value.  The value is converted to signed
     * decimal representation and returned as a string, exactly as if
     * the {@code long} value were given as an argument to the
     * {@link java.lang.Long#toString(long)} method.
     *
     * @return  a string representation of the value of this object in
     *          base&nbsp;10.
     */
    public String toString() {
        return toString(value);
    }

    
Returns a hash code for this Long. The result is the exclusive OR of the two halves of the primitive long value held by this Long object. That is, the hashcode is the value of the expression: 
 (int)(this.longValue()^(this.longValue()>>>32)) 
Returns:
 a hash code value for this object./**
     * Returns a hash code for this {@code Long}. The result is
     * the exclusive OR of the two halves of the primitive
     * {@code long} value held by this {@code Long}
     * object. That is, the hashcode is the value of the expression:
     *
     * <blockquote>
     *  {@code (int)(this.longValue()^(this.longValue()>>>32))}
     * </blockquote>
     *
     * @return  a hash code value for this object.
     */
    @Override
    public int hashCode() {
        return Long.hashCode(value);
    }

    
Returns a hash code for a long value; compatible with Long.hashCode(). 
Params:
value – the value to hash
Returns:
a hash code value for a long value.
Since:
1.8/**
     * Returns a hash code for a {@code long} value; compatible with
     * {@code Long.hashCode()}.
     *
     * @param value the value to hash
     * @return a hash code value for a {@code long} value.
     * @since 1.8
     */
    public static int hashCode(long value) {
        return (int)(value ^ (value >>> 32));
    }

    
Compares this object to the specified object. The result is true if and only if the argument is not null and is a Long object that contains the same long value as this object. 
Params:
obj –   the object to compare with.
Returns:
 true if the objects are the same; false otherwise./**
     * Compares this object to the specified object.  The result is
     * {@code true} if and only if the argument is not
     * {@code null} and is a {@code Long} object that
     * contains the same {@code long} value as this object.
     *
     * @param   obj   the object to compare with.
     * @return  {@code true} if the objects are the same;
     *          {@code false} otherwise.
     */
    public boolean equals(Object obj) {
        if (obj instanceof Long) {
            return value == ((Long)obj).longValue();
        }
        return false;
    }

    
Determines the long value of the system property with the specified name. 
The first argument is treated as the name of a system property. System properties are accessible through the System.getProperty(String) method. The string value of this property is then interpreted as a 
long value using the grammar supported by decode and a Long object representing this value is returned. 
If there is no property with the specified name, if the specified name is empty or null, or if the property does not have the correct numeric format, then null is returned. 
In other words, this method returns a Long object equal to the value of: 
 getLong(nm, null) 
Params:
nm –   property name.
Throws:
SecurityException – for the same reasons as System.getProperty
See Also:
System.getProperty(String)
System.getProperty(String, String)
Returns:
 the Long value of the property./**
     * Determines the {@code long} value of the system property
     * with the specified name.
     *
     * <p>The first argument is treated as the name of a system
     * property.  System properties are accessible through the {@link
     * java.lang.System#getProperty(java.lang.String)} method. The
     * string value of this property is then interpreted as a {@code
     * long} value using the grammar supported by {@link Long#decode decode}
     * and a {@code Long} object representing this value is returned.
     *
     * <p>If there is no property with the specified name, if the
     * specified name is empty or {@code null}, or if the property
     * does not have the correct numeric format, then {@code null} is
     * returned.
     *
     * <p>In other words, this method returns a {@code Long} object
     * equal to the value of:
     *
     * <blockquote>
     *  {@code getLong(nm, null)}
     * </blockquote>
     *
     * @param   nm   property name.
     * @return  the {@code Long} value of the property.
     * @throws  SecurityException for the same reasons as
     *          {@link System#getProperty(String) System.getProperty}
     * @see     java.lang.System#getProperty(java.lang.String)
     * @see     java.lang.System#getProperty(java.lang.String, java.lang.String)
     */
    public static Long getLong(String nm) {
        return getLong(nm, null);
    }

    
Determines the long value of the system property with the specified name. 
The first argument is treated as the name of a system property. System properties are accessible through the System.getProperty(String) method. The string value of this property is then interpreted as a 
long value using the grammar supported by decode and a Long object representing this value is returned. 
The second argument is the default value. A Long object that represents the value of the second argument is returned if there is no property of the specified name, if the property does not have the correct numeric format, or if the specified name is empty or null. 
In other words, this method returns a Long object equal to the value of: 
 getLong(nm, new Long(val)) 
but in practice it may be implemented in a manner such as:
Long result = getLong(nm, null);
return (result == null) ? new Long(val) : result;
 to avoid the unnecessary allocation of a Long object when the default value is not needed. 
Params:
nm –    property name.
val –   default value.
Throws:
SecurityException – for the same reasons as System.getProperty
See Also:
System.getProperty(String)
System.getProperty(String, String)
Returns:
 the Long value of the property./**
     * Determines the {@code long} value of the system property
     * with the specified name.
     *
     * <p>The first argument is treated as the name of a system
     * property.  System properties are accessible through the {@link
     * java.lang.System#getProperty(java.lang.String)} method. The
     * string value of this property is then interpreted as a {@code
     * long} value using the grammar supported by {@link Long#decode decode}
     * and a {@code Long} object representing this value is returned.
     *
     * <p>The second argument is the default value. A {@code Long} object
     * that represents the value of the second argument is returned if there
     * is no property of the specified name, if the property does not have
     * the correct numeric format, or if the specified name is empty or null.
     *
     * <p>In other words, this method returns a {@code Long} object equal
     * to the value of:
     *
     * <blockquote>
     *  {@code getLong(nm, new Long(val))}
     * </blockquote>
     *
     * but in practice it may be implemented in a manner such as:
     *
     * <blockquote><pre>
     * Long result = getLong(nm, null);
     * return (result == null) ? new Long(val) : result;
     * </pre></blockquote>
     *
     * to avoid the unnecessary allocation of a {@code Long} object when
     * the default value is not needed.
     *
     * @param   nm    property name.
     * @param   val   default value.
     * @return  the {@code Long} value of the property.
     * @throws  SecurityException for the same reasons as
     *          {@link System#getProperty(String) System.getProperty}
     * @see     java.lang.System#getProperty(java.lang.String)
     * @see     java.lang.System#getProperty(java.lang.String, java.lang.String)
     */
    public static Long getLong(String nm, long val) {
        Long result = Long.getLong(nm, null);
        return (result == null) ? Long.valueOf(val) : result;
    }

    
Returns the long value of the system property with the specified name. The first argument is treated as the name of a system property. System properties are accessible through the System.getProperty(String) method. The string value of this property is then interpreted as a long value, as per the decode method, and a Long object representing this value is returned; in summary: 

If the property value begins with the two ASCII characters 0x or the ASCII character #, not followed by a minus sign, then the rest of it is parsed as a hexadecimal integer exactly as for the method valueOf(String, int) with radix 16. 
If the property value begins with the ASCII character 0 followed by another character, it is parsed as an octal integer exactly as by the method valueOf(String, int) with radix 8. 
Otherwise the property value is parsed as a decimal integer exactly as by the method valueOf(String, int) with radix 10. 
Note that, in every case, neither L ('\u005Cu004C') nor l ('\u005Cu006C') is permitted to appear at the end of the property value as a type indicator, as would be permitted in Java programming language source code. 
The second argument is the default value. The default value is returned if there is no property of the specified name, if the property does not have the correct numeric format, or if the specified name is empty or null. 
Params:
nm –   property name.
val –   default value.
Throws:
SecurityException – for the same reasons as System.getProperty
See Also:
System.getProperty(String)
System.getProperty(String, String)
Returns:
 the Long value of the property./**
     * Returns the {@code long} value of the system property with
     * the specified name.  The first argument is treated as the name
     * of a system property.  System properties are accessible through
     * the {@link java.lang.System#getProperty(java.lang.String)}
     * method. The string value of this property is then interpreted
     * as a {@code long} value, as per the
     * {@link Long#decode decode} method, and a {@code Long} object
     * representing this value is returned; in summary:
     *
     * <ul>
     * <li>If the property value begins with the two ASCII characters
     * {@code 0x} or the ASCII character {@code #}, not followed by
     * a minus sign, then the rest of it is parsed as a hexadecimal integer
     * exactly as for the method {@link #valueOf(java.lang.String, int)}
     * with radix 16.
     * <li>If the property value begins with the ASCII character
     * {@code 0} followed by another character, it is parsed as
     * an octal integer exactly as by the method {@link
     * #valueOf(java.lang.String, int)} with radix 8.
     * <li>Otherwise the property value is parsed as a decimal
     * integer exactly as by the method
     * {@link #valueOf(java.lang.String, int)} with radix 10.
     * </ul>
     *
     * <p>Note that, in every case, neither {@code L}
     * ({@code '\u005Cu004C'}) nor {@code l}
     * ({@code '\u005Cu006C'}) is permitted to appear at the end
     * of the property value as a type indicator, as would be
     * permitted in Java programming language source code.
     *
     * <p>The second argument is the default value. The default value is
     * returned if there is no property of the specified name, if the
     * property does not have the correct numeric format, or if the
     * specified name is empty or {@code null}.
     *
     * @param   nm   property name.
     * @param   val   default value.
     * @return  the {@code Long} value of the property.
     * @throws  SecurityException for the same reasons as
     *          {@link System#getProperty(String) System.getProperty}
     * @see     System#getProperty(java.lang.String)
     * @see     System#getProperty(java.lang.String, java.lang.String)
     */
    public static Long getLong(String nm, Long val) {
        String v = null;
        try {
            v = System.getProperty(nm);
        } catch (IllegalArgumentException | NullPointerException e) {
        }
        if (v != null) {
            try {
                return Long.decode(v);
            } catch (NumberFormatException e) {
            }
        }
        return val;
    }

    
Compares two Long objects numerically. 
Params:
anotherLong –  the Long to be compared.
Returns:
 the value 0 if this Long is equal to the argument Long; a value less than 0 if this Long is numerically less than the argument Long; and a value greater than 0 if this Long is numerically greater than the argument Long (signed comparison).
Since:
  1.2/**
     * Compares two {@code Long} objects numerically.
     *
     * @param   anotherLong   the {@code Long} to be compared.
     * @return  the value {@code 0} if this {@code Long} is
     *          equal to the argument {@code Long}; a value less than
     *          {@code 0} if this {@code Long} is numerically less
     *          than the argument {@code Long}; and a value greater
     *          than {@code 0} if this {@code Long} is numerically
     *           greater than the argument {@code Long} (signed
     *           comparison).
     * @since   1.2
     */
    public int compareTo(Long anotherLong) {
        return compare(this.value, anotherLong.value);
    }

    
Compares two long values numerically. The value returned is identical to what would be returned by: 
   Long.valueOf(x).compareTo(Long.valueOf(y))

Params:
x – the first long to compare
y – the second long to compare
Returns:
the value 0 if x == y; a value less than 0 if x < y; and a value greater than 0 if x > y
Since:
1.7/**
     * Compares two {@code long} values numerically.
     * The value returned is identical to what would be returned by:
     * <pre>
     *    Long.valueOf(x).compareTo(Long.valueOf(y))
     * </pre>
     *
     * @param  x the first {@code long} to compare
     * @param  y the second {@code long} to compare
     * @return the value {@code 0} if {@code x == y};
     *         a value less than {@code 0} if {@code x < y}; and
     *         a value greater than {@code 0} if {@code x > y}
     * @since 1.7
     */
    public static int compare(long x, long y) {
        return (x < y) ? -1 : ((x == y) ? 0 : 1);
    }

    
Compares two long values numerically treating the values as unsigned. 
Params:
x – the first long to compare
y – the second long to compare
Returns:
the value 0 if x == y; a value less than 0 if x < y as unsigned values; and a value greater than 0 if x > y as unsigned values
Since:
1.8/**
     * Compares two {@code long} values numerically treating the values
     * as unsigned.
     *
     * @param  x the first {@code long} to compare
     * @param  y the second {@code long} to compare
     * @return the value {@code 0} if {@code x == y}; a value less
     *         than {@code 0} if {@code x < y} as unsigned values; and
     *         a value greater than {@code 0} if {@code x > y} as
     *         unsigned values
     * @since 1.8
     */
    public static int compareUnsigned(long x, long y) {
        return compare(x + MIN_VALUE, y + MIN_VALUE);
    }


    
Returns the unsigned quotient of dividing the first argument by
the second where each argument and the result is interpreted as
an unsigned value.
Note that in two's complement arithmetic, the three other basic arithmetic operations of add, subtract, and multiply are bit-wise identical if the two operands are regarded as both being signed or both being unsigned. Therefore separate 
addUnsigned, etc. methods are not provided. 
Params:
dividend – the value to be divided
divisor – the value doing the dividing
See Also:
remainderUnsigned
Returns:
the unsigned quotient of the first argument divided by
the second argument
Since:
1.8/**
     * Returns the unsigned quotient of dividing the first argument by
     * the second where each argument and the result is interpreted as
     * an unsigned value.
     *
     * <p>Note that in two's complement arithmetic, the three other
     * basic arithmetic operations of add, subtract, and multiply are
     * bit-wise identical if the two operands are regarded as both
     * being signed or both being unsigned.  Therefore separate {@code
     * addUnsigned}, etc. methods are not provided.
     *
     * @param dividend the value to be divided
     * @param divisor the value doing the dividing
     * @return the unsigned quotient of the first argument divided by
     * the second argument
     * @see #remainderUnsigned
     * @since 1.8
     */
    public static long divideUnsigned(long dividend, long divisor) {
        if (divisor < 0L) { // signed comparison
            // Answer must be 0 or 1 depending on relative magnitude
            // of dividend and divisor.
            return (compareUnsigned(dividend, divisor)) < 0 ? 0L :1L;
        }

        if (dividend > 0) //  Both inputs non-negative
            return dividend/divisor;
        else {
            /*
             * For simple code, leveraging BigInteger.  Longer and faster
             * code written directly in terms of operations on longs is
             * possible; see "Hacker's Delight" for divide and remainder
             * algorithms.
             */
            return toUnsignedBigInteger(dividend).
                divide(toUnsignedBigInteger(divisor)).longValue();
        }
    }

    
Returns the unsigned remainder from dividing the first argument
by the second where each argument and the result is interpreted
as an unsigned value.
Params:
dividend – the value to be divided
divisor – the value doing the dividing
See Also:
divideUnsigned
Returns:
the unsigned remainder of the first argument divided by
the second argument
Since:
1.8/**
     * Returns the unsigned remainder from dividing the first argument
     * by the second where each argument and the result is interpreted
     * as an unsigned value.
     *
     * @param dividend the value to be divided
     * @param divisor the value doing the dividing
     * @return the unsigned remainder of the first argument divided by
     * the second argument
     * @see #divideUnsigned
     * @since 1.8
     */
    public static long remainderUnsigned(long dividend, long divisor) {
        if (dividend > 0 && divisor > 0) { // signed comparisons
            return dividend % divisor;
        } else {
            if (compareUnsigned(dividend, divisor) < 0) // Avoid explicit check for 0 divisor
                return dividend;
            else
                return toUnsignedBigInteger(dividend).
                    remainder(toUnsignedBigInteger(divisor)).longValue();
        }
    }

    // Bit Twiddling

    
The number of bits used to represent a long value in two's complement binary form. 
Since:
1.5/**
     * The number of bits used to represent a {@code long} value in two's
     * complement binary form.
     *
     * @since 1.5
     */
    @Native public static final int SIZE = 64;

    
The number of bytes used to represent a long value in two's complement binary form. 
Since:
1.8/**
     * The number of bytes used to represent a {@code long} value in two's
     * complement binary form.
     *
     * @since 1.8
     */
    public static final int BYTES = SIZE / Byte.SIZE;

    
Returns a long value with at most a single one-bit, in the position of the highest-order ("leftmost") one-bit in the specified long value. Returns zero if the specified value has no one-bits in its two's complement binary representation, that is, if it is equal to zero. 
Params:
i – the value whose highest one bit is to be computed
Returns:
a long value with a single one-bit, in the position of the highest-order one-bit in the specified value, or zero if the specified value is itself equal to zero.
Since:
1.5/**
     * Returns a {@code long} value with at most a single one-bit, in the
     * position of the highest-order ("leftmost") one-bit in the specified
     * {@code long} value.  Returns zero if the specified value has no
     * one-bits in its two's complement binary representation, that is, if it
     * is equal to zero.
     *
     * @param i the value whose highest one bit is to be computed
     * @return a {@code long} value with a single one-bit, in the position
     *     of the highest-order one-bit in the specified value, or zero if
     *     the specified value is itself equal to zero.
     * @since 1.5
     */
    public static long highestOneBit(long i) {
        return i & (MIN_VALUE >>> numberOfLeadingZeros(i));
    }

    
Returns a long value with at most a single one-bit, in the position of the lowest-order ("rightmost") one-bit in the specified long value. Returns zero if the specified value has no one-bits in its two's complement binary representation, that is, if it is equal to zero. 
Params:
i – the value whose lowest one bit is to be computed
Returns:
a long value with a single one-bit, in the position of the lowest-order one-bit in the specified value, or zero if the specified value is itself equal to zero.
Since:
1.5/**
     * Returns a {@code long} value with at most a single one-bit, in the
     * position of the lowest-order ("rightmost") one-bit in the specified
     * {@code long} value.  Returns zero if the specified value has no
     * one-bits in its two's complement binary representation, that is, if it
     * is equal to zero.
     *
     * @param i the value whose lowest one bit is to be computed
     * @return a {@code long} value with a single one-bit, in the position
     *     of the lowest-order one-bit in the specified value, or zero if
     *     the specified value is itself equal to zero.
     * @since 1.5
     */
    public static long lowestOneBit(long i) {
        // HD, Section 2-1
        return i & -i;
    }

    
Returns the number of zero bits preceding the highest-order ("leftmost") one-bit in the two's complement binary representation of the specified long value. Returns 64 if the specified value has no one-bits in its two's complement representation, in other words if it is equal to zero. 
Note that this method is closely related to the logarithm base 2. For all positive long values x: 

floor(log2(x)) = 63 - numberOfLeadingZeros(x) 
ceil(log2(x)) = 64 - numberOfLeadingZeros(x - 1) 
Params:
i – the value whose number of leading zeros is to be computed
Returns:
the number of zero bits preceding the highest-order ("leftmost") one-bit in the two's complement binary representation of the specified long value, or 64 if the value is equal to zero.
Since:
1.5/**
     * Returns the number of zero bits preceding the highest-order
     * ("leftmost") one-bit in the two's complement binary representation
     * of the specified {@code long} value.  Returns 64 if the
     * specified value has no one-bits in its two's complement representation,
     * in other words if it is equal to zero.
     *
     * <p>Note that this method is closely related to the logarithm base 2.
     * For all positive {@code long} values x:
     * <ul>
     * <li>floor(log<sub>2</sub>(x)) = {@code 63 - numberOfLeadingZeros(x)}
     * <li>ceil(log<sub>2</sub>(x)) = {@code 64 - numberOfLeadingZeros(x - 1)}
     * </ul>
     *
     * @param i the value whose number of leading zeros is to be computed
     * @return the number of zero bits preceding the highest-order
     *     ("leftmost") one-bit in the two's complement binary representation
     *     of the specified {@code long} value, or 64 if the value
     *     is equal to zero.
     * @since 1.5
     */
    @HotSpotIntrinsicCandidate
    public static int numberOfLeadingZeros(long i) {
        int x = (int)(i >>> 32);
        return x == 0 ? 32 + Integer.numberOfLeadingZeros((int)i)
                : Integer.numberOfLeadingZeros(x);
    }

    
Returns the number of zero bits following the lowest-order ("rightmost") one-bit in the two's complement binary representation of the specified long value. Returns 64 if the specified value has no one-bits in its two's complement representation, in other words if it is equal to zero. 
Params:
i – the value whose number of trailing zeros is to be computed
Returns:
the number of zero bits following the lowest-order ("rightmost") one-bit in the two's complement binary representation of the specified long value, or 64 if the value is equal to zero.
Since:
1.5/**
     * Returns the number of zero bits following the lowest-order ("rightmost")
     * one-bit in the two's complement binary representation of the specified
     * {@code long} value.  Returns 64 if the specified value has no
     * one-bits in its two's complement representation, in other words if it is
     * equal to zero.
     *
     * @param i the value whose number of trailing zeros is to be computed
     * @return the number of zero bits following the lowest-order ("rightmost")
     *     one-bit in the two's complement binary representation of the
     *     specified {@code long} value, or 64 if the value is equal
     *     to zero.
     * @since 1.5
     */
    @HotSpotIntrinsicCandidate
    public static int numberOfTrailingZeros(long i) {
        // HD, Figure 5-14
        int x, y;
        if (i == 0) return 64;
        int n = 63;
        y = (int)i; if (y != 0) { n = n -32; x = y; } else x = (int)(i>>>32);
        y = x <<16; if (y != 0) { n = n -16; x = y; }
        y = x << 8; if (y != 0) { n = n - 8; x = y; }
        y = x << 4; if (y != 0) { n = n - 4; x = y; }
        y = x << 2; if (y != 0) { n = n - 2; x = y; }
        return n - ((x << 1) >>> 31);
    }

    
Returns the number of one-bits in the two's complement binary representation of the specified long value. This function is sometimes referred to as the population count.
Params:
i – the value whose bits are to be counted
Returns:
the number of one-bits in the two's complement binary representation of the specified long value.
Since:
1.5/**
     * Returns the number of one-bits in the two's complement binary
     * representation of the specified {@code long} value.  This function is
     * sometimes referred to as the <i>population count</i>.
     *
     * @param i the value whose bits are to be counted
     * @return the number of one-bits in the two's complement binary
     *     representation of the specified {@code long} value.
     * @since 1.5
     */
     @HotSpotIntrinsicCandidate
     public static int bitCount(long i) {
        // HD, Figure 5-2
        i = i - ((i >>> 1) & 0x5555555555555555L);
        i = (i & 0x3333333333333333L) + ((i >>> 2) & 0x3333333333333333L);
        i = (i + (i >>> 4)) & 0x0f0f0f0f0f0f0f0fL;
        i = i + (i >>> 8);
        i = i + (i >>> 16);
        i = i + (i >>> 32);
        return (int)i & 0x7f;
     }

    
Returns the value obtained by rotating the two's complement binary representation of the specified long value left by the specified number of bits. (Bits shifted out of the left hand, or high-order, side reenter on the right, or low-order.) 
Note that left rotation with a negative distance is equivalent to right rotation: rotateLeft(val, -distance) == rotateRight(val,
distance). Note also that rotation by any multiple of 64 is a no-op, so all but the last six bits of the rotation distance can be ignored, even if the distance is negative: rotateLeft(val,
distance) == rotateLeft(val, distance & 0x3F). 
Params:
i – the value whose bits are to be rotated left
distance – the number of bit positions to rotate left
Returns:
the value obtained by rotating the two's complement binary representation of the specified long value left by the specified number of bits.
Since:
1.5/**
     * Returns the value obtained by rotating the two's complement binary
     * representation of the specified {@code long} value left by the
     * specified number of bits.  (Bits shifted out of the left hand, or
     * high-order, side reenter on the right, or low-order.)
     *
     * <p>Note that left rotation with a negative distance is equivalent to
     * right rotation: {@code rotateLeft(val, -distance) == rotateRight(val,
     * distance)}.  Note also that rotation by any multiple of 64 is a
     * no-op, so all but the last six bits of the rotation distance can be
     * ignored, even if the distance is negative: {@code rotateLeft(val,
     * distance) == rotateLeft(val, distance & 0x3F)}.
     *
     * @param i the value whose bits are to be rotated left
     * @param distance the number of bit positions to rotate left
     * @return the value obtained by rotating the two's complement binary
     *     representation of the specified {@code long} value left by the
     *     specified number of bits.
     * @since 1.5
     */
    public static long rotateLeft(long i, int distance) {
        return (i << distance) | (i >>> -distance);
    }

    
Returns the value obtained by rotating the two's complement binary representation of the specified long value right by the specified number of bits. (Bits shifted out of the right hand, or low-order, side reenter on the left, or high-order.) 
Note that right rotation with a negative distance is equivalent to left rotation: rotateRight(val, -distance) == rotateLeft(val,
distance). Note also that rotation by any multiple of 64 is a no-op, so all but the last six bits of the rotation distance can be ignored, even if the distance is negative: rotateRight(val,
distance) == rotateRight(val, distance & 0x3F). 
Params:
i – the value whose bits are to be rotated right
distance – the number of bit positions to rotate right
Returns:
the value obtained by rotating the two's complement binary representation of the specified long value right by the specified number of bits.
Since:
1.5/**
     * Returns the value obtained by rotating the two's complement binary
     * representation of the specified {@code long} value right by the
     * specified number of bits.  (Bits shifted out of the right hand, or
     * low-order, side reenter on the left, or high-order.)
     *
     * <p>Note that right rotation with a negative distance is equivalent to
     * left rotation: {@code rotateRight(val, -distance) == rotateLeft(val,
     * distance)}.  Note also that rotation by any multiple of 64 is a
     * no-op, so all but the last six bits of the rotation distance can be
     * ignored, even if the distance is negative: {@code rotateRight(val,
     * distance) == rotateRight(val, distance & 0x3F)}.
     *
     * @param i the value whose bits are to be rotated right
     * @param distance the number of bit positions to rotate right
     * @return the value obtained by rotating the two's complement binary
     *     representation of the specified {@code long} value right by the
     *     specified number of bits.
     * @since 1.5
     */
    public static long rotateRight(long i, int distance) {
        return (i >>> distance) | (i << -distance);
    }

    
Returns the value obtained by reversing the order of the bits in the two's complement binary representation of the specified long value. 
Params:
i – the value to be reversed
Returns:
the value obtained by reversing order of the bits in the specified long value.
Since:
1.5/**
     * Returns the value obtained by reversing the order of the bits in the
     * two's complement binary representation of the specified {@code long}
     * value.
     *
     * @param i the value to be reversed
     * @return the value obtained by reversing order of the bits in the
     *     specified {@code long} value.
     * @since 1.5
     */
    public static long reverse(long i) {
        // HD, Figure 7-1
        i = (i & 0x5555555555555555L) << 1 | (i >>> 1) & 0x5555555555555555L;
        i = (i & 0x3333333333333333L) << 2 | (i >>> 2) & 0x3333333333333333L;
        i = (i & 0x0f0f0f0f0f0f0f0fL) << 4 | (i >>> 4) & 0x0f0f0f0f0f0f0f0fL;

        return reverseBytes(i);
    }

    
Returns the signum function of the specified long value. (The return value is -1 if the specified value is negative; 0 if the specified value is zero; and 1 if the specified value is positive.) 
Params:
i – the value whose signum is to be computed
Returns:
the signum function of the specified long value.
Since:
1.5/**
     * Returns the signum function of the specified {@code long} value.  (The
     * return value is -1 if the specified value is negative; 0 if the
     * specified value is zero; and 1 if the specified value is positive.)
     *
     * @param i the value whose signum is to be computed
     * @return the signum function of the specified {@code long} value.
     * @since 1.5
     */
    public static int signum(long i) {
        // HD, Section 2-7
        return (int) ((i >> 63) | (-i >>> 63));
    }

    
Returns the value obtained by reversing the order of the bytes in the two's complement representation of the specified long value. 
Params:
i – the value whose bytes are to be reversed
Returns:
the value obtained by reversing the bytes in the specified long value.
Since:
1.5/**
     * Returns the value obtained by reversing the order of the bytes in the
     * two's complement representation of the specified {@code long} value.
     *
     * @param i the value whose bytes are to be reversed
     * @return the value obtained by reversing the bytes in the specified
     *     {@code long} value.
     * @since 1.5
     */
    @HotSpotIntrinsicCandidate
    public static long reverseBytes(long i) {
        i = (i & 0x00ff00ff00ff00ffL) << 8 | (i >>> 8) & 0x00ff00ff00ff00ffL;
        return (i << 48) | ((i & 0xffff0000L) << 16) |
            ((i >>> 16) & 0xffff0000L) | (i >>> 48);
    }

    
Adds two long values together as per the + operator. 
Params:
a – the first operand
b – the second operand
See Also:
BinaryOperator
Returns:
the sum of a and b
Since:
1.8/**
     * Adds two {@code long} values together as per the + operator.
     *
     * @param a the first operand
     * @param b the second operand
     * @return the sum of {@code a} and {@code b}
     * @see java.util.function.BinaryOperator
     * @since 1.8
     */
    public static long sum(long a, long b) {
        return a + b;
    }

    
Returns the greater of two long values as if by calling Math.max. 
Params:
a – the first operand
b – the second operand
See Also:
BinaryOperator
Returns:
the greater of a and b
Since:
1.8/**
     * Returns the greater of two {@code long} values
     * as if by calling {@link Math#max(long, long) Math.max}.
     *
     * @param a the first operand
     * @param b the second operand
     * @return the greater of {@code a} and {@code b}
     * @see java.util.function.BinaryOperator
     * @since 1.8
     */
    public static long max(long a, long b) {
        return Math.max(a, b);
    }

    
Returns the smaller of two long values as if by calling Math.min. 
Params:
a – the first operand
b – the second operand
See Also:
BinaryOperator
Returns:
the smaller of a and b
Since:
1.8/**
     * Returns the smaller of two {@code long} values
     * as if by calling {@link Math#min(long, long) Math.min}.
     *
     * @param a the first operand
     * @param b the second operand
     * @return the smaller of {@code a} and {@code b}
     * @see java.util.function.BinaryOperator
     * @since 1.8
     */
    public static long min(long a, long b) {
        return Math.min(a, b);
    }

    
use serialVersionUID from JDK 1.0.2 for interoperability /** use serialVersionUID from JDK 1.0.2 for interoperability */
    @Native private static final long serialVersionUID = 4290774380558885855L;
}