/* * This file is part of JSTUN.  *  * Copyright (c) 2005 Thomas King <king@t-king.de> - All rights * reserved. *  * This software is licensed under either the GNU Public License (GPL), * or the Apache 2.0 license. Copies of both license agreements are * included in this distribution. */package de.javawi.jstun.util;public class Utility {	public static final byte IntegerToOneByte(int value) throws UtilityException {		if ((value > Math.pow(2,15)) || (value < 0)) {			throw new UtilityException("Integer value " + value + " is larger than 2^15");		}		return (byte)(value & 0xFF);	}		public static final byte[] IntegerToTwoBytes(int value) throws UtilityException {		byte[] result = new byte[2];		if ((value > Math.pow(2,31)) || (value < 0)) {			throw new UtilityException("Integer value " + value + " is larger than 2^31");		}        result[0] = (byte)((value >>> 8) & 0xFF);        result[1] = (byte)(value & 0xFF);		return result; 	}		public static final byte[] IntegerToFourBytes(int value) throws UtilityException {		byte[] result = new byte[4];		if ((value > Math.pow(2,63)) || (value < 0)) {			throw new UtilityException("Integer value " + value + " is larger than 2^63");		}        result[0] = (byte)((value >>> 24) & 0xFF);		result[1] = (byte)((value >>> 16) & 0xFF);		result[2] = (byte)((value >>> 8) & 0xFF);        result[3] = (byte)(value & 0xFF);		return result; 	}		public static final int OneByteToInteger(byte value) throws UtilityException {		return (int)value & 0xFF;	}		public static final int TwoBytesToInteger(byte[] value) throws UtilityException {		if (value.length < 2) {			throw new UtilityException("Byte array too short!");		}        int temp0 = value[0] & 0xFF;        int temp1 = value[1] & 0xFF;        return ((temp0 << 8) + temp1);	}		public static final long FourBytesToLong(byte[] value) throws UtilityException {		if (value.length < 4) {			throw new UtilityException("Byte array too short!");		}        int temp0 = value[0] & 0xFF;        int temp1 = value[1] & 0xFF;		int temp2 = value[2] & 0xFF;		int temp3 = value[3] & 0xFF;        return (((long)temp0 << 24) + (temp1 << 16) + (temp2 << 8) + temp3);	}	                                      }