设计登陆表， 两次MD5加密

<dependency>
  <groupId>commons-codec</groupId>
  <artifactId>commons-codec</artifactId>
</dependency>
<dependency>
  <groupId>org.apache.commons</groupId>
  <artifactId>commons-lang3</artifactId>
  <version>3.6</version>
</dependency>

package com.*.*.util;

import org.apache.commons.codec.digest.DigestUtils;

public class MD5Util {
    
    public static String md5(String src) {
        return DigestUtils.md5Hex(src);
    }
    
    private static final String salt = "1a2b3c4d";
    
    public static String inputPassToFormPass(String inputPass) {
        String str = ""+salt.charAt(0)+salt.charAt(2) + inputPass +salt.charAt(5) + salt.charAt(4);
        System.out.println(str);
        return md5(str);
    }
    
    public static String formPassToDBPass(String formPass, String salt) {
        String str = ""+salt.charAt(0)+salt.charAt(2) + formPass +salt.charAt(5) + salt.charAt(4);
        return md5(str);
    }
    
    public static String inputPassToDbPass(String inputPass, String saltDB) {
        String formPass = inputPassToFormPass(inputPass);
        String dbPass = formPassToDBPass(formPass, saltDB);
        return dbPass;
    }
    
    public static void main(String[] args) {
        System.out.println(inputPassToFormPass("123456"));//d3b1294a61a07da9b49b6e22b2cbd7f9
//      System.out.println(formPassToDBPass(inputPassToFormPass("123456"), "1a2b3c4d"));
//      System.out.println(inputPassToDbPass("123456", "1a2b3c4d"));//b7797cce01b4b131b433b6acf4add449
    }
    
}