java Md5 加密

import java.security.MessageDigest;


/**
 * MD5加密类
 * 
 */
public class MD5Encoding
{
	/**
	 * 
	 * 
	 */
	private MD5Encoding()
	{
	}


	/**
	 * 加密算法MD5
	 * 
	 * @param text
	 *            明文
	 * @return String 密文
	 */
	public final static String encoding(String text)
	{
		char hexDigits[] =
		{ '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd',
				'e', 'f' };
		String encodingStr = null;
		try
		{
			byte[] strTemp = text.getBytes();
			MessageDigest mdTemp = MessageDigest.getInstance("MD5");
			mdTemp.update(strTemp);
			byte[] md = mdTemp.digest();
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++)
			{
				byte byte0 = md[i];
				str[k++] = hexDigits[byte0 >>> 4 & 0xf];
				str[k++] = hexDigits[byte0 & 0xf];
			}
			encodingStr = new String(str);
		}
		catch (Exception e)
		{
		}
		return encodingStr;
	}


	public static void main(String[] areg)
	{
		MD5Encoding md5 = new MD5Encoding();
		md5.encoding("admin");
	}
}

原文来自：http://www.cnblogs.com/bmbm/archive/2011/12/06/2342262.html