1     public void save(Student student) {

         // TODO Auto-generated method stub
       student.setSid(UUID.randomUUID().toString());

         student.setPwd(MD5Util.md5(student.getPwd()));

         studentRepository.save(student);

     }

 package com.bw.utils;

 import java.security.MessageDigest;

 import java.security.NoSuchAlgorithmException;

 public class MD5Util {

     public static String md5(String passwd) {

         StringBuffer md5Str = new StringBuffer();

         try {

             MessageDigest md5 = MessageDigest.getInstance("MD5");

             byte[] digest = md5.digest(passwd.getBytes());

             for (byte b : digest) {

                 md5Str.append(String.format("%02x", b));

             }

         } catch (NoSuchAlgorithmException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         }

         return md5Str.toString();

     }

 }