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	/*
	* Copyright (c) 1996, 2013, 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 jdk.internal.HotSpotIntrinsicCandidate;

	/**
	*
	* 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 1.1
	*/
	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}.
	*/
	@SuppressWarnings("unchecked")
	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
	*/
	@HotSpotIntrinsicCandidate
	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 '\u005Cu002D'}) to indicate a negative value or an
	* ASCII plus sign {@code '+'} ({@code '\u005Cu002B'}) 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 '\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 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 '\u005Cu002D'}) to indicate a negative
	* value or an ASCII plus sign {@code '+'}
	* ({@code '\u005Cu002B'}) 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>
	*
	* <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™ 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}.
	*
	* @deprecated
	* It is rarely appropriate to use this constructor. The static factory
	* {@link #valueOf(byte)} is generally a better choice, as it is
	* likely to yield significantly better space and time performance.
	*/
	@Deprecated(since="9")
	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}.
	*
	* @deprecated
	* It is rarely appropriate to use this constructor.
	* Use {@link #parseByte(String)} to convert a string to a
	* {@code byte} primitive, or use {@link #valueOf(String)}
	* to convert a string to a {@code Byte} object.
	*/
	@Deprecated(since="9")
	public Byte(String s) throws NumberFormatException {
	this.value = parseByte(s, 10);
	}

	/**
	* Returns the value of this {@code Byte} as a
	* {@code byte}.
	*/
	@HotSpotIntrinsicCandidate
	public byte byteValue() {
	return value;
	}

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

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

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

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

	/**
	* Returns a hash code for a {@code byte} value; compatible with
	* {@code Byte.hashCode()}.
	*
	* @param value the value to hash
	* @return a hash code value for a {@code byte} value.
	* @since 1.8
	*/
	public static int hashCode(byte value) {
	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;
	}

	/**
	* Compares two {@code byte} values numerically treating the values
	* as unsigned.
	*
	* @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} as unsigned values; and
	* a value greater than {@code 0} if {@code x > y} as
	* unsigned values
	* @since 9
	*/
	public static int compareUnsigned(byte x, byte y) {
	return Byte.toUnsignedInt(x) - Byte.toUnsignedInt(y);
	}

	/**
	* Converts the argument to an {@code int} by an unsigned
	* conversion. In an unsigned conversion to an {@code int}, the
	* high-order 24 bits of the {@code int} are zero and the
	* low-order 8 bits are equal to the bits of the {@code byte} argument.
	*
	* Consequently, zero and positive {@code byte} values are mapped
	* to a numerically equal {@code int} value and negative {@code
	* byte} values are mapped to an {@code int} value equal to the
	* input plus 2<sup>8</sup>.
	*
	* @param x the value to convert to an unsigned {@code int}
	* @return the argument converted to {@code int} by an unsigned
	* conversion
	* @since 1.8
	*/
	public static int toUnsignedInt(byte x) {
	return ((int) x) & 0xff;
	}

	/**
	* Converts the argument to a {@code long} by an unsigned
	* conversion. In an unsigned conversion to a {@code long}, the
	* high-order 56 bits of the {@code long} are zero and the
	* low-order 8 bits are equal to the bits of the {@code byte} argument.
	*
	* Consequently, zero and positive {@code byte} values are mapped
	* to a numerically equal {@code long} value and negative {@code
	* byte} values are mapped to a {@code long} value equal to the
	* input plus 2<sup>8</sup>.
	*
	* @param x the value to convert to an unsigned {@code long}
	* @return the argument converted to {@code long} by an unsigned
	* conversion
	* @since 1.8
	*/
	public static long toUnsignedLong(byte x) {
	return ((long) x) & 0xffL;
	}


	/**
	* 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;

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

	/** use serialVersionUID from JDK 1.1. for interoperability */
	private static final long serialVersionUID = -7183698231559129828L;
	}

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