MD5.java

package com.dgrid.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5 {
	private static final char kHexChars[] = { '0', '1', '2', '3', '4', '5',
			'6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

	public static String md5(String text) {
		return md5(text.getBytes());
	}

	public static String md5(byte[] bytes) {
		try {
			MessageDigest md = MessageDigest.getInstance("MD5");
			md.update(bytes);
			return MD5.bufferToHex(md.digest());
		} catch (NoSuchAlgorithmException e) {
			throw (new RuntimeException(e));
		}
	}

	private static String bufferToHex(byte buffer[]) {
		return MD5.bufferToHex(buffer, 0, buffer.length);
	}

	private static String bufferToHex(byte buffer[], int startOffset, int length) {
		StringBuffer hexString = new StringBuffer(2 * length);
		int endOffset = startOffset + length;

		for (int i = startOffset; i < endOffset; i++)
			MD5.appendHexPair(buffer[i], hexString);

		return hexString.toString();
	}

	private static void appendHexPair(byte b, StringBuffer hexString) {
		char highNibble = kHexChars[(b & 0xF0) >> 4];
		char lowNibble = kHexChars[b & 0x0F];

		hexString.append(highNibble);
		hexString.append(lowNibble);
	}
}