Java工具类：（3）MD5加密

package com.rk.utils;

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

public class Md5Utils
{
private Md5Utils()
{
}

public static String Md5(String plainText)
{
try
{
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(plainText.getBytes());
byte b[] = md.digest();
int i;
StringBuffer buf = new StringBuffer("");
for (int offset = 0; offset < b.length; offset++)
{
i = b[offset];
if (i < 0)
i += 256;
if (i < 16)
buf.append("0");
buf.append(Integer.toHexString(i));
}
return buf.toString();
}
catch (NoSuchAlgorithmException e)
{
throw new RuntimeException("服务器错误 :" + e);
}
}
}