Java模塊系列:MD5

1 MD5簡介

信息-摘要算法（Message-digest Algorithm 5，MD5）於90年代初由MIT Labortory for computer sicence和RSA data security inc的ronald l.rivest開發，經md2、md3和md4發展而來。MD5的典型應用是對一段信息（message）產生信息摘要（message-digest），防止信息被篡改，常應用於加密和解密技術、Unix系統中。

2 Usage

2.1 Java原始生成MD5

package basic.datatype.dataprocess;

import java.security.MessageDigest;

public class MD5SecurityUtil {
    public static String genMD5ByRaw(String str){
        try{
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            byte[] digest = md5.digest(str.getBytes("UTF-8"));
            String md5Str = "";
            for(int i=0;i<digest.length;i++){
                md5Str += Integer.toHexString((0x000000FF&digest[i])|0xFFFFFF00).substring(6); 
            }
            return md5Str;

        }catch(Exception e){
            e.printStackTrace();
        }
        return "ERROR";
    }

    public static void main(String[] args){
        String md5ByRaw = genMD5ByRaw("str");
        System.out.println("md5 by raw:"+md5ByRaw);
    } 
}

2.2 Java數學處理生成MD5

package basic.datatype.dataprocess;

import java.security.MessageDigest;
import java.math.BigInteger;

public class MD5SecurityUtil {
    public static String genMD5ByMath(String str){
        try{
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            md5.update(str.getBytes());
            // byte[] digest = md5.digest(str.getBytes("utf-8"));
            String md5Str = new BigInteger(1, md5.digest()).toString(16);
            return md5Str;
        }catch(Exception e){
            e.printStackTrace();
        }
        return "ERROR";
    }

    public static void main(String[] args){
        String md5 = genMD5ByMath("str");
        System.out.println("md5 by math:"+md5);
    } 
}

2.3 Spring生成MD5

package com.company.workordersystem.service;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.DigestUtils;
import java.util.Map;
import java.util.HashMap;


@Service
@Transactional
public class UNPlusService {
    @Value("${unplus.url}")
    private String unplusUrl;

    public String genMD5(String currentTime){
        String SID = "WY_YT";
        String spliceData = unplusUrl + currentTime + SID;
        String md5 = DigestUtils.md5DigestAsHex(spliceData.getBytes());
        return md5;
    }

    public Map submitWorkorderToUNPlus(Map reqCont, Map svcCont){
        Map<String, String> returnMap = new HashMap<>();
        Map<String, Object> bodyMap = new HashMap<>();
        bodyMap.put("ReqCont", reqCont);
        bodyMap.put("SvcCont", svcCont);
        bodyMap.put("optType", "addWorkInfo");
        return bodyMap;
        // return returnMap;
    }  
}

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【參考文獻】
[1]https://blog.csdn.net/qq_30683329/article/details/80879058
[2]https://www.cnblogs.com/chinaifae/p/10188535.html
[3]https://blog.csdn.net/junmoxi/article/details/80841555