public static String md555(String plainText) throws UnsupportedEncodingException {

 byte[] secretBytes = null;

 try {

 secretBytes = MessageDigest.getInstance("md5").digest(

 plainText.getBytes());

 } catch (NoSuchAlgorithmException e) {

 throw new RuntimeException("没有md5这个算法！");

 }

 String md5code = new BigInteger(1, secretBytes).toString(16);// 16进制数字

 // 如果生成数字未满32位，需要前面补0

 for (int i = 0; i < 32 - md5code.length(); i++) {

 md5code = "0" + md5code;

 }

 return md5code;

 }