UnsignedByte.java

/*
 * RED5 Open Source Flash Server - http://code.google.com/p/red5/
 * 
 * Copyright 2006-2012 by respective authors (see below). All rights reserved.
 * 
 * Licensed 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 org.red5.io.object;

/**
 * The UnsignedByte class wraps a value of and unsigned 8 bits number.
 * 
 * @author Matteo Merli (matteo.merli@gmail.com)
 */
public final class UnsignedByte extends UnsignedNumber {
	static final long serialVersionUID = 1L;

	private short value;

	public UnsignedByte(byte c) {
		value = c;
	}

	public UnsignedByte(short c) {
		value = (short) (c & 0xFF);
	}

	public UnsignedByte(int c) {
		value = (short) (c & 0xFF);
	}

	public UnsignedByte(long c) {
		value = (short) (c & 0xFFL);
	}

	private UnsignedByte() {
		value = 0;
	}

	public static UnsignedByte fromBytes(byte[] c) {
		return fromBytes(c, 0);
	}

	public static UnsignedByte fromBytes(byte[] c, int idx) {
		UnsignedByte number = new UnsignedByte();
		if ((c.length - idx) < 1)
			throw new IllegalArgumentException(
					"An UnsignedByte number is composed of 1 byte.");

		number.value = (short) (c[0] & 0xFF);
		return number;
	}

	public static UnsignedByte fromString(String c) {
		return fromString(c, 10);
	}

	public static UnsignedByte fromString(String c, int radix) {
		UnsignedByte number = new UnsignedByte();

		short v = Short.parseShort(c, radix);
		number.value = (short) (v & 0xFF);
		return number;
	}

	@Override
	public double doubleValue() {
		return value;
	}

	@Override
	public float floatValue() {
		return value;
	}

	@Override
	public short shortValue() {
		return (short) (value & 0xFF);
	}

	@Override
	public int intValue() {
		return value & 0xFF;
	}

	@Override
	public long longValue() {
		return value & 0xFFL;
	}

	@Override
	public byte[] getBytes() {
		byte[] c = { (byte) (value & 0xFF) };
		return c;
	}

	@Override
	public int compareTo(UnsignedNumber other) {
		short otherValue = other.shortValue();
		if (value > otherValue) {
			return +1;
		} else if (value < otherValue) {
			return -1;
		}
		return 0;
	}

	@Override
	public boolean equals(Object other) {
		if (other != null && other instanceof Number) {
			return value == ((Number) other).shortValue();
		} else {
			return false;
		}
	}
	
	@Override
	public int hashCode() { 
		return value;
	}

	@Override
	public String toString() {
		return Short.toString(value);
	}

	@Override
	public void shiftRight(int nBits) {
		if (Math.abs(nBits) > 8) {
			throw new IllegalArgumentException("Cannot right shift " + nBits
					+ " an UnsignedByte.");
		}
		value >>>= nBits;
	}

	@Override
	public void shiftLeft(int nBits) {
		if (Math.abs(nBits) > 8) {
			throw new IllegalArgumentException("Cannot left shift " + nBits
					+ " an UnsignedByte.");
		}
		value <<= nBits;
	}
}