java 的md5加密算法源代码.txt

JAVA 的MD5加密算法源代码 JAVA 的MD5加密算法源代码

package com.yizhi.gcbgl;
import java.security.*;
import java.security.spec.*;

/*
检验你的实现是否正确： 
MD5 ("") = d41d8cd98f00b204e9800998ecf8427e 
MD5 ("a") = 0cc175b9c0f1b6a831c399e269772661 
MD5 ("abc") = 900150983cd24fb0d6963f7d28e17f72 
MD5 ("message digest") = f96b697d7cb7938d525a2f31aaf161d0 
MD5 ("abcdefghijklmnopqrstuvwxyz") = c3fcd3d76192e4007dfb496cca67e13b
*/


class md5_test{



public final static String md5(String s)
{
	char hexDigits[] ={'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
						'a', 'b', 'c', 'd', 'e', 'f'};

	try 
	{
		byte[] strtemp = s.getBytes();
		MessageDigest mdtemp = MessageDigest.getInstance("MD5");
		mdtemp.update(strtemp);
		byte[] md = mdtemp.digest();
		int j = md.length;
		char str[] = new char[j * 2];
		int k = 0;
		for (int i = 0; i < j; i++ ) 
		{
			byte byte0 = md[i];
			str[k ] = hexDigits[byte0 >>> 4 & 0xf];
			str[k ] = hexDigits[byte0 & 0xf];
		}
		return new String(str);
	}
	catch (Exception e)
	{
		return null;
	}
	}
	public static void main(String[] args)
	{
		//md5_test aa = new md5_test();



		System.out.print(md5_test.md5("xx"));
	}

}