/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package java.lang; /** * The wrapper for the primitive type {@code byte}. * * @since 1.1 */ @FindBugsSuppressWarnings("DM_NUMBER_CTOR") public final class Byte extends Number implements Comparable<Byte> { private static final long serialVersionUID = -7183698231559129828L; /** * The value which the receiver represents. */ private final byte value; /** * The maximum {@code Byte} value, 2<sup>7</sup>-1. */ public static final byte MAX_VALUE = (byte) 0x7F; /** * The minimum {@code Byte} value, -2<sup>7</sup>. */ public static final byte MIN_VALUE = (byte) 0x80; /** * The number of bits needed to represent a {@code Byte} value in two's * complement form. * * @since 1.5 */ public static final int SIZE = 8; /** * The {@link Class} object that represents the primitive type {@code byte}. */ @SuppressWarnings("unchecked") public static final Class<Byte> TYPE = (Class<Byte>) byte[].class.getComponentType(); // Note: Byte.TYPE can't be set to "byte.class", since *that* is // defined to be "java.lang.Byte.TYPE"; /** * Constructs a new {@code Byte} with the specified primitive byte value. * * @param value * the primitive byte value to store in the new instance. */ public Byte(byte value) { this.value = value; } /** * Constructs a new {@code Byte} from the specified string. * * @param string * the string representation of a single byte value. * @throws NumberFormatException * if {@code string} cannot be parsed as a byte value. * @see #parseByte(String) */ public Byte(String string) throws NumberFormatException { this(parseByte(string)); } /** * Gets the primitive value of this byte. * * @return this object's primitive value. */ @Override public byte byteValue() { return value; } /** * Compares this object to the specified byte object to determine their * relative order. * * @param object * the byte object to compare this object to. * @return a negative value if the value of this byte is less than the value * of {@code object}; 0 if the value of this byte and the value of * {@code object} are equal; a positive value if the value of this * byte is greater than the value of {@code object}. * @see java.lang.Comparable * @since 1.2 */ public int compareTo(Byte object) { return compare(value, object.value); } /** * Compares two {@code byte} values. * @return 0 if lhs = rhs, less than 0 if lhs < rhs, and greater than 0 if lhs > rhs. * @since 1.7 * @hide 1.7 */ public static int compare(byte lhs, byte rhs) { return lhs > rhs ? 1 : (lhs < rhs ? -1 : 0); } /** * Parses the specified string and returns a {@code Byte} instance if the * string can be decoded into a single byte value. The string may be an * optional minus sign "-" followed by a hexadecimal ("0x..." or "#..."), * octal ("0..."), or decimal ("...") representation of a byte. * * @param string * a string representation of a single byte value. * @return a {@code Byte} containing the value represented by {@code string}. * @throws NumberFormatException * if {@code string} cannot be parsed as a byte value. */ public static Byte decode(String string) throws NumberFormatException { int intValue = Integer.decode(string); byte result = (byte) intValue; if (result == intValue) { return valueOf(result); } throw new NumberFormatException("Value out of range for byte: \"" + string + "\""); } @Override public double doubleValue() { return value; } /** * Compares this object with the specified object and indicates if they are * equal. In order to be equal, {@code object} must be an instance of * {@code Byte} and have the same byte value as this object. * * @param object * the object to compare this byte with. * @return {@code true} if the specified object is equal to this * {@code Byte}; {@code false} otherwise. */ @Override @FindBugsSuppressWarnings("RC_REF_COMPARISON") public boolean equals(Object object) { return (object == this) || ((object instanceof Byte) && (((Byte) object).value == value)); } @Override public float floatValue() { return value; } @Override public int hashCode() { return value; } @Override public int intValue() { return value; } @Override public long longValue() { return value; } /** * Parses the specified string as a signed decimal byte value. The ASCII * character \u002d ('-') is recognized as the minus sign. * * @param string * the string representation of a single byte value. * @return the primitive byte value represented by {@code string}. * @throws NumberFormatException * if {@code string} can not be parsed as a byte value. */ public static byte parseByte(String string) throws NumberFormatException { return parseByte(string, 10); } /** * Parses the specified string as a signed byte value using the specified * radix. The ASCII character \u002d ('-') is recognized as the minus sign. * * @param string * the string representation of a single byte value. * @param radix * the radix to use when parsing. * @return the primitive byte value represented by {@code string} using * {@code radix}. * @throws NumberFormatException * if {@code string} can not be parsed as a byte value, or * {@code radix < Character.MIN_RADIX || * radix > Character.MAX_RADIX}. */ public static byte parseByte(String string, int radix) throws NumberFormatException { int intValue = Integer.parseInt(string, radix); byte result = (byte) intValue; if (result == intValue) { return result; } throw new NumberFormatException("Value out of range for byte: \"" + string + "\""); } @Override public short shortValue() { return value; } @Override public String toString() { return Integer.toString(value); } /** * Returns a two-digit hex string. That is, -1 becomes "ff" or "FF" and 2 becomes "02". * @hide internal use only */ public static String toHexString(byte b, boolean upperCase) { return IntegralToString.byteToHexString(b, upperCase); } /** * Returns a string containing a concise, human-readable description of the * specified byte value. * * @param value * the byte to convert to a string. * @return a printable representation of {@code value}. */ public static String toString(byte value) { return Integer.toString(value); } /** * Parses the specified string as a signed decimal byte value. * * @param string * the string representation of a single byte value. * @return a {@code Byte} instance containing the byte value represented by * {@code string}. * @throws NumberFormatException * if {@code string} can not be parsed as a byte value. * @see #parseByte(String) */ public static Byte valueOf(String string) throws NumberFormatException { return valueOf(parseByte(string)); } /** * Parses the specified string as a signed byte value using the specified * radix. * * @param string * the string representation of a single byte value. * @param radix * the radix to use when parsing. * @return a {@code Byte} instance containing the byte value represented by * {@code string} using {@code radix}. * @throws NumberFormatException * if {@code string} can not be parsed as a byte value, or * {@code radix < Character.MIN_RADIX || * radix > Character.MAX_RADIX}. * @see #parseByte(String, int) */ public static Byte valueOf(String string, int radix) throws NumberFormatException { return valueOf(parseByte(string, radix)); } /** * Returns a {@code Byte} instance for the specified byte value. * <p> * If it is not necessary to get a new {@code Byte} instance, it is * recommended to use this method instead of the constructor, since it * maintains a cache of instances which may result in better performance. * * @param b * the byte value to store in the instance. * @return a {@code Byte} instance containing {@code b}. * @since 1.5 */ public static Byte valueOf(byte b) { return VALUES[b + 128]; } /** * A cache of instances used by {@link Byte#valueOf(byte)} and auto-boxing */ private static final Byte[] VALUES = new Byte[256]; static { for (int i = -128; i < 128; i++) { VALUES[i + 128] = new Byte((byte) i); } } }