如何在JAVA中使用MD5加密对密码进行加密

package com.loger.md5;import java.io.UnsupportedEncodingException;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException;import sun.misc.BASE64Encoder;public class Md5 {     public String EncoderByMd5(String str) throws NoSuchAlgorithmException, UnsupportedEncodingException{    //确定计算方法    MessageDigest md5=MessageDigest.getInstance("MD5");    BASE64Encoder base64en = new BASE64Encoder();    //加密后的字符串    String newstr=base64en.encode(md5.digest(str.getBytes("utf-8")));    return newstr;  }      public boolean checkpassword(String newpasswd,String oldpasswd) throws NoSuchAlgorithmException, UnsupportedEncodingException{    if(EncoderByMd5(newpasswd).equals(oldpasswd))      return true;    else      return false;  }}