/*

 * Copyright (c) 1994, 2009, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package java.lang;

import org.apidesign.bck2brwsr.core.JavaScriptBody;

/**

 * 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   JDK1.0

 */

public final class Long extends Number implements Comparable<Long> {

    /**

     * A constant holding the minimum value a {@code long} can

     * have, -2<sup>63</sup>.

     */

    public static final long MIN_VALUE = 0x8000000000000000L;

    /**

     * A constant holding the maximum value a {@code long} can

     * have, 2<sup>63</sup>-1.

     */

    public static final long MAX_VALUE = 0x7fffffffffffffffL;

    /**

     * The {@code Class} instance representing the primitive type

     * {@code long}.

     *

     * @since   JDK1.1

     */

    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.

     *

     * <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>'&#92;u002d'</code>). 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>'&#92;u0030'</code>); 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>'&#92;u0030'</code> through

     * <code>'&#92;u0039'</code> and <code>'&#92;u0061'</code> through

     * <code>'&#92;u007a'</code>. 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);

        char[] buf = new char[65];

        int charPos = 64;

        boolean negative = (i < 0);

        if (!negative) {

            i = -i;

        }

        while (i <= -radix) {

            buf[charPos--] = Integer.digits[(int)(-(i % radix))];

            i = i / radix;

        }

        buf[charPos] = Integer.digits[(int)(-i)];

        if (negative) {

            buf[--charPos] = '-';

        }

        return new String(buf, charPos, (65 - charPos));

    }

    /**

     * Returns a string representation of the {@code long}

     * argument as an unsigned integer in base 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 16) with no extra

     * leading {@code 0}s.  If the unsigned magnitude is zero, it

     * is represented by a single zero character {@code '0'}

     * (<code>'&#92;u0030'</code>); 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>'&#92;u0030'</code> through

     * <code>'&#92;u0039'</code> and  <code>'&#92;u0061'</code> through

     * <code>'&#92;u0066'</code>.  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 16).

     * @since   JDK 1.0.2

     */

    public static String toHexString(long i) {

        return toUnsignedString(i, 4);

    }

    /**

     * Returns a string representation of the {@code long}

     * argument as an unsigned integer in base 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 8) with no extra leading

     * {@code 0}s.

     *

     * <p>If the unsigned magnitude is zero, it is represented by a

     * single zero character {@code '0'}

     * (<code>'&#92;u0030'</code>); 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>'&#92;u0030'</code> through

     * <code>'&#92;u0037'</code>.

     *

     * @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 8).

     * @since   JDK 1.0.2

     */

    public static String toOctalString(long i) {

        return toUnsignedString(i, 3);

    }

    /**

     * Returns a string representation of the {@code long}

     * argument as an unsigned integer in base 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 2) with no extra leading

     * {@code 0}s.  If the unsigned magnitude is zero, it is

     * represented by a single zero character {@code '0'}

     * (<code>'&#92;u0030'</code>); otherwise, the first character of

     * the representation of the unsigned magnitude will not be the

     * zero character. The characters {@code '0'}

     * (<code>'&#92;u0030'</code>) and {@code '1'}

     * (<code>'&#92;u0031'</code>) 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 2).

     * @since   JDK 1.0.2

     */

    public static String toBinaryString(long i) {

        return toUnsignedString(i, 1);

    }

    /**

     * Convert the integer to an unsigned number.

     */

    private static String toUnsignedString(long i, int shift) {

        char[] buf = new char[64];

        int charPos = 64;

        int radix = 1 << shift;

        long mask = radix - 1;

        do {

            buf[--charPos] = Integer.digits[(int)(i & mask)];

            i >>>= shift;

        } while (i != 0);

        return new String(buf, charPos, (64 - charPos));

    }

    /**

     * 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 10.

     */

    @JavaScriptBody(args = "i", body = "return i.toString();")

    public static String toString(long i) {

        if (i == Long.MIN_VALUE)

            return "-9223372036854775808";

        int size = (i < 0) ? stringSize(-i) + 1 : stringSize(i);

        char[] buf = new char[size];

        getChars(i, size, buf);

        return new String(buf, 0, size);

    }

    /**

     * Places characters representing the integer 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.

     *

     * Will fail if i == Long.MIN_VALUE

     */

    static void getChars(long i, int index, char[] buf) {

        long q;

        int r;

        int charPos = index;

        char sign = 0;

        if (i < 0) {

            sign = '-';

            i = -i;

        }

        // Get 2 digits/iteration using longs until quotient fits into an int

        while (i > Integer.MAX_VALUE) {

            q = i / 100;

            // really: r = i - (q * 100);

            r = (int)(i - ((q << 6) + (q << 5) + (q << 2)));

            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 >= 65536) {

            q2 = i2 / 100;

            // really: r = i2 - (q * 100);

            r = i2 - ((q2 << 6) + (q2 << 5) + (q2 << 2));

            i2 = q2;

            buf[--charPos] = Integer.DigitOnes[r];

            buf[--charPos] = Integer.DigitTens[r];

        }

        // Fall thru to fast mode for smaller numbers

        // assert(i2 <= 65536, i2);

        for (;;) {

            q2 = (i2 * 52429) >>> (16+3);

            r = i2 - ((q2 << 3) + (q2 << 1));  // r = i2-(q2*10) ...

            buf[--charPos] = Integer.digits[r];

            i2 = q2;

            if (i2 == 0) break;

        }

        if (sign != 0) {

            buf[--charPos] = sign;

        }

    }

    // Requires positive x

    static int stringSize(long x) {

        long p = 10;

        for (int i=1; i<19; i++) {

            if (x < p)

                return i;

            p = 10*p;

        }

        return 19;

    }

    /**

     * 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>'&#92;u002D'</code>) to

     * indicate a negative value or an ASCII plus sign {@code '+'}

     * (<code>'&#92;u002B'</code>) to indicate a positive value. The

     * resulting {@code long} value is returned.

     *

     * <p>Note that neither the character {@code L}

     * (<code>'&#92;u004C'</code>) nor {@code l}

     * (<code>'&#92;u006C'</code>) 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 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>'&#92;u002d'</code>) or plus sign {@code

     * '+'} (<code>'&#92;u002B'</code>) 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");

        }

        long result = 0;

        boolean negative = false;

        int i = 0, len = s.length();

        long limit = -Long.MAX_VALUE;

        long multmin;

        int digit;

        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++;

            }

            multmin = limit / radix;

            while (i < len) {

                // Accumulating negatively avoids surprises near MAX_VALUE

                digit = Character.digit(s.charAt(i++),radix);

                if (digit < 0) {

                    throw NumberFormatException.forInputString(s);

                }

                if (result < multmin) {

                    throw NumberFormatException.forInputString(s);

                }

                result *= radix;

                if (result < limit + digit) {

                    throw NumberFormatException.forInputString(s);

                }

                result -= digit;

            }

        } else {

            throw NumberFormatException.forInputString(s);

        }

        return negative ? result : -result;

    }

    /**

     * 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>&#92;u002D'</code>) to indicate a negative value or an

     * ASCII plus sign {@code '+'} (<code>'&#92;u002B'</code>) 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>'&#92;u004C'</code>) nor {@code l}

     * (<code>'&#92;u006C'</code>) 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);

    }

    /**

     * 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 {@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 {@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.

     *

     * Note that unlike the {@linkplain Integer#valueOf(int)

     * corresponding method} in the {@code Integer} class, this method

     * is <em>not</em> required to cache values within a particular

     * range.

     *

     * @param  l a long value.

     * @return a {@code Long} instance representing {@code l}.

     * @since  1.5

     */

    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 {@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>

     * <p>

     * <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.length() == 0)

            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 {@code Long}.

     *

     * @serial

     */

    private final long value;

    /**

     * 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.

     */

    public Long(long value) {

        this.value = value;

    }

    /**

     * 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}.

     * @see        java.lang.Long#parseLong(java.lang.String, int)

     */

    public Long(String s) throws NumberFormatException {

        this.value = parseLong(s, 10);

    }

    /**

     * Returns the value of this {@code Long} as a

     * {@code byte}.

     */

    public byte byteValue() {

        return (byte)value;

    }

    /**

     * Returns the value of this {@code Long} as a

     * {@code short}.

     */

    public short shortValue() {

        return (short)value;

    }

    /**

     * Returns the value of this {@code Long} as an

     * {@code int}.

     */

    public int intValue() {

        return (int)value;

    }

    /**

     * Returns the value of this {@code Long} as a

     * {@code long} value.

     */

    public long longValue() {

        return (long)value;

    }

    /**

     * Returns the value of this {@code Long} as a

     * {@code float}.

     */

    public float floatValue() {

        return (float)value;

    }

    /**

     * Returns the value of this {@code Long} as a

     * {@code double}.

     */

    public double doubleValue() {

        return (double)value;

    }

    /**

     * 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 10.

     */

    public String toString() {

        return toString(value);

    }

    /**

     * 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.

     */

    public int hashCode() {

        return (int)(value ^ (value >>> 32));

    }

    /**

     * 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 {@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 and a {@code Long} object

     * representing this value is returned.  Details of possible

     * numeric formats can be found with the definition of

     * {@code getProperty}.

     *

     * <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.

     * @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 {@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 and a {@code Long} object

     * representing this value is returned.  Details of possible

     * numeric formats can be found with the definition of

     * {@code getProperty}.

     *

     * <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.

     * @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 {@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

     * {@code Long.decode} method, and a {@code Long} object

     * representing this value is returned.

     *

     * <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>'&#92;u004C'</code>) nor {@code l}

     * (<code>'&#92;u006C'</code>) 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.

     * @see     java.lang.System#getProperty(java.lang.String)

     * @see java.lang.System#getProperty(java.lang.String, java.lang.String)

     * @see java.lang.Long#decode

     */

    public static Long getLong(String nm, Long val) {

        String v = null;

        try {

            v = AbstractStringBuilder.getProperty(nm);

        } catch (IllegalArgumentException e) {

        } catch (NullPointerException e) {

        }

        if (v != null) {

            try {

                return Long.decode(v);

            } catch (NumberFormatException e) {

            }

        }

        return val;

    }

    /**

     * 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 {@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);

    }

    // Bit Twiddling

    /**

     * The number of bits used to represent a {@code long} value in two's

     * complement binary form.

     *

     * @since 1.5

     */

    public static final int SIZE = 64;

    /**

     * 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.