/*

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  * 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;

 /**

  *

  * The {@code Byte} class wraps a value of primitive type {@code byte}

  * in an object.  An object of type {@code Byte} contains a single

  * field whose type is {@code byte}.

  *

  * <p>In addition, this class provides several methods for converting

  * a {@code byte} to a {@code String} and a {@code String} to a {@code

  * byte}, as well as other constants and methods useful when dealing

  * with a {@code byte}.

  *

  * @author  Nakul Saraiya

  * @author  Joseph D. Darcy

  * @see     java.lang.Number

  * @since   JDK1.1

  */

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

     /**

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

      * have, -2<sup>7</sup>.

      */

     public static final byte   MIN_VALUE = -128;

     /**

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

      * have, 2<sup>7</sup>-1.

      */

     public static final byte   MAX_VALUE = 127;

     /**

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

      * {@code byte}.

      */

     public static final Class<Byte>     TYPE = (Class<Byte>) Class.getPrimitiveClass("byte");

     /**

      * Returns a new {@code String} object representing the

      * specified {@code byte}. The radix is assumed to be 10.

      *

      * @param b the {@code byte} to be converted

      * @return the string representation of the specified {@code byte}

      * @see java.lang.Integer#toString(int)

      */

     public static String toString(byte b) {

         return Integer.toString((int)b, 10);

     }

     private static class ByteCache {

         private ByteCache(){}

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

         static {

             for(int i = 0; i < cache.length; i++)

                 cache[i] = new Byte((byte)(i - 128));

         }

     }

     /**

      * Returns a {@code Byte} instance representing the specified

      * {@code byte} value.

      * If a new {@code Byte} instance is not required, this method

      * should generally be used in preference to the constructor

      * {@link #Byte(byte)}, as this method is likely to yield

      * significantly better space and time performance since

      * all byte values are cached.

      *

      * @param  b a byte value.

      * @return a {@code Byte} instance representing {@code b}.

      * @since  1.5

      */

     public static Byte valueOf(byte b) {

         final int offset = 128;

         return ByteCache.cache[(int)b + offset];

     }

     /**

      * Parses the string argument as a signed {@code byte} 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 byte} 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 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 byte}.

      * </ul>

      *

      * @param s         the {@code String} containing the

      *                  {@code byte}

      *                  representation to be parsed

      * @param radix     the radix to be used while parsing {@code s}

      * @return          the {@code byte} value represented by the string

      *                   argument in the specified radix

      * @throws          NumberFormatException If the string does

      *                  not contain a parsable {@code byte}.

      */

     public static byte parseByte(String s, int radix)

         throws NumberFormatException {

         int i = Integer.parseInt(s, radix);

         if (i < MIN_VALUE || i > MAX_VALUE)

             throw new NumberFormatException(

                 "Value out of range. Value:\"" + s + "\" Radix:" + radix);

         return (byte)i;

     }

     /**

      * Parses the string argument as a signed decimal {@code

      * byte}. 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 byte} value is returned, exactly as if the

      * argument and the radix 10 were given as arguments to the {@link

      * #parseByte(java.lang.String, int)} method.

      *

      * @param s         a {@code String} containing the

      *                  {@code byte} representation to be parsed

      * @return          the {@code byte} value represented by the

      *                  argument in decimal

      * @throws          NumberFormatException if the string does not

      *                  contain a parsable {@code byte}.

      */

     public static byte parseByte(String s) throws NumberFormatException {

         return parseByte(s, 10);

     }

     /**

      * Returns a {@code Byte} 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 byte} in

      * the radix specified by the second argument, exactly as if the

      * argument were given to the {@link #parseByte(java.lang.String,

      * int)} method. The result is a {@code Byte} object that

      * represents the {@code byte} value specified by the string.

      *

      * <p> In other words, this method returns a {@code Byte} object

      * equal to the value of:

      *

      * <blockquote>

      * {@code new Byte(Byte.parseByte(s, radix))}

      * </blockquote>

      *

      * @param s         the string to be parsed

      * @param radix     the radix to be used in interpreting {@code s}

      * @return          a {@code Byte} 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 byte}.

      */

     public static Byte valueOf(String s, int radix)

         throws NumberFormatException {

         return valueOf(parseByte(s, radix));

     }

     /**

      * Returns a {@code Byte} object holding the value

      * given by the specified {@code String}. The argument is

      * interpreted as representing a signed decimal {@code byte},

      * exactly as if the argument were given to the {@link

      * #parseByte(java.lang.String)} method. The result is a

      * {@code Byte} object that represents the {@code byte}

      * value specified by the string.

      *

      * <p> In other words, this method returns a {@code Byte} object

      * equal to the value of:

      *

      * <blockquote>

      * {@code new Byte(Byte.parseByte(s))}

      * </blockquote>

      *

      * @param s         the string to be parsed

      * @return          a {@code Byte} object holding the value

      *                  represented by the string argument

      * @throws          NumberFormatException If the {@code String} does

      *                  not contain a parsable {@code byte}.

      */

     public static Byte valueOf(String s) throws NumberFormatException {

         return valueOf(s, 10);

     }

     /**

      * Decodes a {@code String} into a {@code Byte}.

      * 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

      * Byte.parseByte} 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 Byte} object holding the {@code byte}

      *          value represented by {@code nm}

      * @throws  NumberFormatException  if the {@code String} does not

      *            contain a parsable {@code byte}.

      * @see java.lang.Byte#parseByte(java.lang.String, int)

      */

     public static Byte decode(String nm) throws NumberFormatException {

         int i = Integer.decode(nm);

         if (i < MIN_VALUE || i > MAX_VALUE)

             throw new NumberFormatException(

                     "Value " + i + " out of range from input " + nm);

         return valueOf((byte)i);

     }

     /**

      * The value of the {@code Byte}.

      *

      * @serial

      */

     private final byte value;

     /**

      * Constructs a newly allocated {@code Byte} object that

      * represents the specified {@code byte} value.

      *

      * @param value     the value to be represented by the

      *                  {@code Byte}.

      */

     public Byte(byte value) {

         this.value = value;

     }

     /**

      * Constructs a newly allocated {@code Byte} object that

      * represents the {@code byte} value indicated by the

      * {@code String} parameter. The string is converted to a

      * {@code byte} value in exactly the manner used by the

      * {@code parseByte} method for radix 10.

      *

      * @param s         the {@code String} to be converted to a

      *                  {@code Byte}

      * @throws           NumberFormatException If the {@code String}

      *                  does not contain a parsable {@code byte}.

      * @see        java.lang.Byte#parseByte(java.lang.String, int)

      */

     public Byte(String s) throws NumberFormatException {

         this.value = parseByte(s, 10);

     }

     /**

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

      * {@code byte}.

      */

     public byte byteValue() {

         return value;

     }

     /**

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

      * {@code short}.

      */

     public short shortValue() {

         return (short)value;

     }

     /**

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

      * {@code int}.

      */

     public int intValue() {

         return (int)value;

     }

     /**

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

      * {@code long}.

      */

     public long longValue() {

         return (long)value;

     }

     /**

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

      * {@code float}.

      */

     public float floatValue() {

         return (float)value;

     }

     /**

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

      * {@code double}.

      */

     public double doubleValue() {

         return (double)value;

     }

     /**

      * Returns a {@code String} object representing this

      * {@code Byte}'s value.  The value is converted to signed

      * decimal representation and returned as a string, exactly as if

      * the {@code byte} value were given as an argument to the

      * {@link java.lang.Byte#toString(byte)} method.

      *

      * @return  a string representation of the value of this object in

      *          base 10.

      */

     public String toString() {

         return Integer.toString((int)value);

     }

     /**

      * Returns a hash code for this {@code Byte}; equal to the result

      * of invoking {@code intValue()}.

      *

      * @return a hash code value for this {@code Byte}

      */

     public int hashCode() {

         return (int)value;

     }

     /**

      * 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 Byte} object that

      * contains the same {@code byte} 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 Byte) {

             return value == ((Byte)obj).byteValue();

         }

         return false;

     }

     /**

      * Compares two {@code Byte} objects numerically.

      *

      * @param   anotherByte   the {@code Byte} to be compared.

      * @return  the value {@code 0} if this {@code Byte} is

      *          equal to the argument {@code Byte}; a value less than

      *          {@code 0} if this {@code Byte} is numerically less

      *          than the argument {@code Byte}; and a value greater than

      *           {@code 0} if this {@code Byte} is numerically

      *           greater than the argument {@code Byte} (signed

      *           comparison).

      * @since   1.2

      */

     public int compareTo(Byte anotherByte) {

         return compare(this.value, anotherByte.value);

     }

     /**

      * Compares two {@code byte} values numerically.

      * The value returned is identical to what would be returned by:

      * <pre>

      *    Byte.valueOf(x).compareTo(Byte.valueOf(y))

      * </pre>

      *

      * @param  x the first {@code byte} to compare

      * @param  y the second {@code byte} 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(byte x, byte y) {

         return x - y;

     }

     /**

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

      * complement binary form.

      *

      * @since 1.5

      */

     public static final int SIZE = 8;

     /** use serialVersionUID from JDK 1.1. for interoperability */

     private static final long serialVersionUID = -7183698231559129828L;

 }