用hash去存储用户密码

1.db2的function：

create function tvc.pwdEncrypt(password varchar(20))
returns varchar(90)
fenced
threadsafe
deterministic
allow parallel
no sql
returns null on null input
no external action
language java
parameter style java
external name 'com.ibm.mbps.tvc.util.TvcPwdEncrypt!pwdEncrypt';

2./*
* OCO Source Materials
*
* Licensed Materials -
*
* 5747-SM3
*
* (C) Copyright Corp. 2011 All Rights Reserved.
*
* US Government Users Restricted Rights - Use, duplication or
* disclosure restricted by Schedule Contract with IBM Corp.
*/

package com.xxx.mbps.tvc.util;

import java.security.MessageDigest;

import COM.ibm.db2.app.UDF;

import com.ibm.misc.BASE64Encoder;

public class TvcPwdEncrypt extends UDF {
public static String pwdEncrypt(String password) {
if (password == null) {
return null;
}

try {
MessageDigest md = MessageDigest.getInstance("SHA512");
byte[] input = password.trim().getBytes();
md.update(input);
byte[] buf = md.digest();
BASE64Encoder be = new BASE64Encoder();
String result = be.encode(buf);
// remove \r \n
result = result.replaceAll("\n", "").replaceAll("\r", "");
return result;
} catch (Exception e) {
return null;
}
}
}