Java 通用md5工具类

java 封装的MD5工具包，兼容PHP的MD5函数，代码如下：

1package main.blog.utils;
2
3import java.security.MessageDigest;
4import java.security.NoSuchAlgorithmException;
5
6public class Md5Util 
7{
8    public static String md5(String buffer)
9    {
10        String string       = null;
11        char hexDigist[] = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};
12        MessageDigest md;
13        try {
14            md = MessageDigest.getInstance("MD5");
15            md.update(buffer.getBytes());
16            byte[] datas = md.digest(); //16个字节的长整数
17            
18            char[] str = new char[2*16];
19            int k = 0;
20            
21            for(int i=0;i<16;i++)
22            {
23              byte b   = datas[i];
24              str[k++] = hexDigist[b>>>4 & 0xf];//高4位
25              str[k++] = hexDigist[b & 0xf];//低4位
26            }
27            string = new String(str);
28        } catch (NoSuchAlgorithmException e) 
29        {
30            e.printStackTrace();
31        }
32        return string;
33    }
34}