package com.cirle.scientific.utils.weixin;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/*
 * MD5 算法
*/
public class MD5 {
    
    // 全局数组
    private final static String[] strDigits = { "0", "1", "2", "3", "4", "5",
            "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

    public MD5() {
    }

    // 返回形式为数字跟字符串
    private static String byteToArrayString(byte bByte) {
        int iRet = bByte;
        // System.out.println("iRet="+iRet);
        if (iRet < 0) {
            iRet += 256;
        }
        int iD1 = iRet / 16;
        int iD2 = iRet % 16;
        return strDigits[iD1] + strDigits[iD2];
    }

    // 转换字节数组为16进制字串
    private static String byteToString(byte[] bByte) {
        StringBuffer sBuffer = new StringBuffer();
        for (int i = 0; i < bByte.length; i++) {
            sBuffer.append(byteToArrayString(bByte[i]));
        }
        return sBuffer.toString();
    }

    public static String getStringToMD5(String strObj) {
        String resultString = null;
        try {
            resultString = new String(strObj);
            MessageDigest md = MessageDigest.getInstance("MD5");
            // md.digest() 该函数返回值为存放哈希值结果的byte数组
            resultString = byteToString(md.digest(strObj.getBytes("UTF-8")));
        } catch (NoSuchAlgorithmException ex) {
            ex.printStackTrace();
        } catch (UnsupportedEncodingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
        return resultString;
    }

    public static void main(String[] args) {
        
        System.out.println(getStringToMD5("appid=wx5951befda9896890&body=Ipad&mch_id=1237075402&nonce_str=e50d45c8751a4c7b8075b8c9238e43d8&notify_url=www.baidu.com&out_trade_no=123456789&product_id=b9a217b11554475181dca32ad2f1fda1&spbill_create_ip=127.0.0.1&total_fee=1&trade_type=NATIVE&key=b9a217b11554475181dca32ad2f1fda9").toUpperCase());
    }
}