/*
* Tanaguru - Automated webpage assessment
* Copyright (C) 2008-2015 Tanaguru.org
*
* This file is part of Tanaguru.
*
* Tanaguru is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Contact us by mail: tanaguru AT tanaguru DOT org
*/
package org.tanaguru.util;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
*
* @author jkowalczyk
*/
public class MD5Encoder {
private static final String MD5 = "MD5";
private static final String UTF_8_ENCODING = "UTF-8";
/**
* Default private constructor
*/
private MD5Encoder() {}
/**
*
* @param data
* @return
*/
private static String convertToHex(byte[] data) {
StringBuilder buf = new StringBuilder();
for (int i = 0; i < data.length; i++) {
int halfbyte = (data[i] >>> 4) & 0x0F;
int two_halfs = 0;
do {
if ((0 <= halfbyte) && (halfbyte <= 9)) {
buf.append((char) ('0' + halfbyte));
} else {
buf.append((char) ('a' + (halfbyte - 10)));
}
halfbyte = data[i] & 0x0F;
} while (two_halfs++ < 1);
}
String md5 = buf.toString();
buf.delete(0, buf.length()-1);
return md5;
}
/**
* Converts a given string as a MD5 encoded string.
*
* @param text
* @return
* @throws NoSuchAlgorithmException
* @throws UnsupportedEncodingException
*/
public static String MD5(String text)
throws NoSuchAlgorithmException, UnsupportedEncodingException {
MessageDigest md;
md = MessageDigest.getInstance(MD5);
md.update(text.getBytes(UTF_8_ENCODING), 0, text.length());
return convertToHex(md.digest());
}
}