/*
* Copyright (c) 2009 Lockheed Martin Corporation
*
* 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.eurekastreams.server.service.actions.strategies;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Random;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* Generates a unique hash for every input using the magic of MD5 and a random
* number seed.
*
*/
public class HashGeneratorStrategy
{
/**
* Logggger.
*/
private Log log = LogFactory.getLog(HashGeneratorStrategy.class);
/**
* Has to be here for magic number reasons. Bleh.
*/
private static final int TWO_FIFTY_FIVE = 0xFF;
/**
* Hashs an input.
*
* @param inInput
* the input string.
* @return the output string.
*/
public String hash(final String inInput)
{
Random generator = new Random();
String input = inInput + Integer.toString(generator.nextInt());
try
{
MessageDigest algorithm = MessageDigest.getInstance("MD5");
algorithm.reset();
algorithm.update(input.getBytes());
byte[] messageDigest = algorithm.digest();
StringBuffer hexString = new StringBuffer();
for (int i = 0; i < messageDigest.length; i++)
{
hexString.append(Integer.toHexString(TWO_FIFTY_FIVE & messageDigest[i]));
}
return hexString.toString();
}
catch (NoSuchAlgorithmException e)
{
log.error("hash failed");
return null;
}
}
}