/*
* GNU LESSER GENERAL PUBLIC LICENSE Copyright (C) 2006 The Lobo Project
*
* This library is free software; you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License as published by the Free
* Software Foundation; either version 2.1 of the License, or (at your option)
* any later version.
*
* This library 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 Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Contact info: lobochief@users.sourceforge.net
*/
/*
* Created on Jun 7, 2005
*/
package com.nvarghese.beowulf.common.cobra.util;
import java.math.BigInteger;
import java.net.InetAddress;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* @author J. H. S.
*/
public class ID {
private static final Random RANDOM1;
private static final Random RANDOM2;
private static final Random RANDOM3;
private static final long globalProcessID;
private static final Logger logger = Logger.getLogger(ID.class.getName());
static {
long time = System.currentTimeMillis();
long nanoTime = System.nanoTime();
long freeMemory = Runtime.getRuntime().freeMemory();
long addressHashCode;
try {
InetAddress inetAddress;
inetAddress = InetAddress.getLocalHost();
addressHashCode = inetAddress.getHostName().hashCode() ^ inetAddress.getHostAddress().hashCode();
} catch (Exception err) {
logger.log(Level.WARNING, "Unable to get local host information.", err);
addressHashCode = ID.class.hashCode();
}
globalProcessID = time ^ nanoTime ^ freeMemory ^ addressHashCode;
RANDOM1 = new Random(time);
RANDOM2 = new Random(nanoTime);
RANDOM3 = new Random(addressHashCode ^ freeMemory);
}
private ID() {
}
public static long generateLong() {
return Math.abs(RANDOM1.nextLong() ^ RANDOM2.nextLong() ^ RANDOM3.nextLong());
}
public static int generateInt() {
return (int) generateLong();
}
public static byte[] getMD5Bytes(final String content) {
try {
MessageDigest digest = MessageDigest.getInstance("MD5");
return digest.digest(content.getBytes("UTF-8"));
} catch (NoSuchAlgorithmException e) {
throw new IllegalStateException(e);
} catch (java.io.UnsupportedEncodingException uee) {
throw new IllegalStateException(uee);
}
}
public static String getHexString(final byte[] bytes) {
// This method cannot change even if it's wrong.
BigInteger bigInteger = BigInteger.ZERO;
int shift = 0;
for (int i = bytes.length; --i >= 0;) {
BigInteger contrib = BigInteger.valueOf(bytes[i] & 0xFF);
contrib = contrib.shiftLeft(shift);
bigInteger = bigInteger.add(contrib);
shift += 8;
}
return bigInteger.toString(16).toUpperCase();
}
/**
* Gets a process ID that is nearly guaranteed to be globally unique.
*/
public static long getGlobalProcessID() {
return globalProcessID;
}
public static int random(final int min, final int max) {
if (max <= min) {
return min;
}
return (RANDOM1.nextInt()) % (max - min) + min;
}
}