md5.java

：一个用JavaScript开发的用户管理系统。

package test;
import java.security.*; 
import java.security.spec.*;
import java.math.*; 
public class MD5{ 
    public String convert32(String s){ 
        char hexChars[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'}; 
        try { 
            byte[] bytes = s.getBytes(); 
            MessageDigest md = MessageDigest.getInstance("MD5"); 
            md.update(bytes); 
            bytes = md.digest();     
            int j = bytes.length; 
            char[] chars = new char[j * 2]; 
            int k = 0; 
            for (int i = 0; i < bytes.length; i++) { 
                byte b = bytes[i]; 
                chars[k++] = hexChars[b >>> 4 & 0xf]; 
                chars[k++] = hexChars[b & 0xf]; 
            } 
            return new String(chars);             
        } 
        catch (Exception e){ 
            return null; 
        } 
    } 
    public String convert16(String s){
       String ns=convert32(s).substring(8,24);
       return ns;  
    }
/*   
    public static void main(String[] args){
        System.out.println(new MD5().convert32("0123456789"));  
        System.out.println(new MD5().convert16("0123456789"));       
    }
*/
}