MySql数据库级别MD5加密java MD5加密解密工具包

测试MD5 加密

CREATE TABLE `testmd5`(
   `id` INT(4) NOT NULL,
   `name` VARCHAR(20) NOT NULL,
   `pwd` VARCHAR(50) NOT NULL,
   PRIMARY KEY(`id`)
)ENGINE=INNODB DEFAULT CHARSET=utf8

-- 明文密码
INSERT INTO testmd5 VALUES(1,'zhangsan','123456'),(2,'lisi','123456'),(3,'wangwu','123456')

-- 加密
UPDATE testmd5 SET pwd=MD5(pwd) WHERE id = 1

UPDATE testmd5 SET pwd=MD5(pwd)  -- 加密全部的密码

-- 插入的时候加密
INSERT INTO testmd5 VALUES(4,'xiaoming',MD5('123456'))

-- 如何校验：将用户传递进来的密码，进行md5加密，然后比对加密后的值
SELECT * FROM testmd5 WHERE `name`='xiaoming' AND pwd=MD5('123456')

import java.security.MessageDigest;


public class MD5Util {  
  
    /*** 
     * MD5加码 生成32位md5码 
     */  
    public static String string2MD5(String inStr){  
        MessageDigest md5 = null;
        try{  
            md5 = MessageDigest.getInstance("MD5");  
        }catch (Exception e){  
            System.out.println(e.toString());  
            e.printStackTrace();  
            return "";  
        }  
        char[] charArray = inStr.toCharArray();  
        byte[] byteArray = new byte[charArray.length];  
  
        for (int i = 0; i < charArray.length; i++)  
            byteArray[i] = (byte) charArray[i];  
        byte[] md5Bytes = md5.digest(byteArray);  
        StringBuffer hexValue = new StringBuffer();  
        for (int i = 0; i < md5Bytes.length; i++){  
            int val = ((int) md5Bytes[i]) & 0xff;  
            if (val < 16)  
                hexValue.append("0");  
            hexValue.append(Integer.toHexString(val));  
        }  
        return hexValue.toString();  
  
    }  
  
    /** 
     * 加密解密算法 执行一次加密，两次解密 
     */   
    public static String convertMD5(String inStr){  
  
        char[] a = inStr.toCharArray();  
        for (int i = 0; i < a.length; i++){  
            a[i] = (char) (a[i] ^ 't');  
        }  
        String s = new String(a);  
        return s;  
  
    }  
  
    // 测试主函数  
    public static void main(String args[]) {  
        String s = new String("tangfuqiang");  
        System.out.println("原始：" + s);  
        System.out.println("MD5后：" + string2MD5(s));  
        System.out.println("加密的：" + convertMD5(s));  
        System.out.println("解密的：" + convertMD5(convertMD5(s)));  
  
    }  
}