/*
 * Copyright (c) 1996, 2011, 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;

/**
 *
 * 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;

	/*
	 * NANITE: This is a change from OpenJDK in that the class type is setup by the linker so we don't create it here
	 */

	/**
	 * The {@code Class} instance representing the primitive type
	 * {@code byte}.
	 */
	public static final Class<Byte>     TYPE = null;

	/**
	 * 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);
	}

	/* NANITE: Removing cache to save memory */
	/*
	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) {
		/* NANITE: Removing cache to save memory */
		//final int offset = 128;
		//return ByteCache.cache[(int)b + offset];
		return new Byte(b);
	}

	/**
	 * 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} 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&nbsp;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;
}
