MD5加密（简写）

直接贴代码吧：

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class Md5 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        
        String str = "";
        MessageDigest md5 = null;
        try {
            md5 = MessageDigest.getInstance("MD5");
            //返回实现指定摘要算法的 MessageDigest对象
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            System.out.println("error");
        }
        
        char[] charArray = str.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));
        }
        System.out.println("md5 code:"+hexValue.toString());
        
    }

}