/*
* 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 Android 1.0
*/
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.
*
* @since Android 1.0
*/
public static final byte MAX_VALUE = (byte) 0x7F;
/**
* The minimum {@code Byte} value, -2<sup>7</sup>.
*
* @since Android 1.0
*/
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 Android 1.0
*/
public static final int SIZE = 8;
/**
* The {@link Class} object that represents the primitive type {@code byte}.
*
* @since Android 1.0
*/
@SuppressWarnings("unchecked")
public static final Class<Byte> TYPE = (Class<Byte>) new byte[0].getClass()
.getComponentType();
// Note: This can't be set to "byte.class", since *that* is
// defined to be "java.lang.Byte.TYPE";
/**
* A cache of instances used by {@link #valueOf(byte)} and auto-boxing.
*/
private static final Byte[] CACHE = new Byte[256];
/**
* Constructs a new {@code Byte} with the specified primitive byte value.
*
* @param value
* the primitive byte value to store in the new instance.
* @since Android 1.0
*/
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} can not be decoded into a byte value.
* @see #parseByte(String)
* @since Android 1.0
*/
public Byte(String string) throws NumberFormatException {
this(parseByte(string));
}
/**
* Gets the primitive value of this byte.
*
* @return this object's primitive value.
* @since Android 1.0
*/
@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 Android 1.0
*/
public int compareTo(Byte object) {
return value > object.value ? 1 : (value < object.value ? -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} can not be parsed as a byte value.
* @since Android 1.0
*/
public static Byte decode(String string) throws NumberFormatException {
int intValue = Integer.decode(string).intValue();
byte result = (byte) intValue;
if (result == intValue) {
return valueOf(result);
}
throw new NumberFormatException();
}
@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.
* @since Android 1.0
*/
@Override
public boolean equals(Object object) {
return (object == this) || (object instanceof Byte)
&& (value == ((Byte) object).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} is {@code null}, has a length of zero or
* can not be parsed as a byte value.
* @since Android 1.0
*/
public static byte parseByte(String string) throws NumberFormatException {
int intValue = Integer.parseInt(string);
byte result = (byte) intValue;
if (result == intValue) {
return result;
}
throw new NumberFormatException();
}
/**
* 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} is {@code null} or has a length of zero,
* {@code radix < Character.MIN_RADIX},
* {@code radix > Character.MAX_RADIX}, or if {@code string}
* can not be parsed as a byte value.
* @since Android 1.0
*/
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();
}
@Override
public short shortValue() {
return value;
}
@Override
public String toString() {
return Integer.toString(value);
}
/**
* 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}.
* @since Android 1.0
*/
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} is {@code null}, has a length of zero or
* can not be parsed as a byte value.
* @see #parseByte(String)
* @since Android 1.0
*/
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} is {@code null} or has a length of zero,
* {@code radix < Character.MIN_RADIX},
* {@code radix > Character.MAX_RADIX}, or if {@code string}
* can not be parsed as a byte value.
* @see #parseByte(String, int)
* @since Android 1.0
*/
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.
* </p>
*
* @param b
* the byte value to store in the instance.
* @return a {@code Byte} instance containing {@code b}.
* @since Android 1.0
*/
public static Byte valueOf(byte b) {
synchronized (CACHE) {
int idx = b - MIN_VALUE;
Byte result = CACHE[idx];
return (result == null ? CACHE[idx] = new Byte(b) : result);
}
}
}
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