數字加密在專案中時常會遇到，如手機號，身份證號資訊等，下面小白將自己手寫的數字加密演算法分享給大家，可在專案中直接運用.
加密規則，入參時傳遞一個欄位時間戳 time：
*  1.以字母代替數字，0-9分別為["D","e","C","A","#","b","J","I","z","M"]
* 2.混淆字母為FxYNgq;
* 3.加密字串等於初始數字加時間戳乘以數字金鑰（5658116）再把數字結果轉換成字母；
* 4.對於加密字串長度小於總加密字串長度（32）的隨機插入混淆字母
例：(15755141030 + 1544769549545)*5658116=8829629720137456700-->再轉換成字母 
 
qFzzYFCMJYqCMgICDNxFeAqI#bJgIFDD;

package com.example.demo.t2;
import java.util.regex.Pattern;

/**
 * Created by ypf on 2018/12/14.
 */
public class Test {

    //數字祕鑰
    private final static long SECRET_KEY = 5658116;
    //轉換字元（0-9分別為["D","e","C","A","#","b","J","I","z","M"]
    private final static String CONVERT_KEY = "DeCA#bJIzM";
    
 
//混淆字母
    private final static String CONFUSED_WORDS_KEY = "FxYNgq";
    //總加密字串長度
    private final static int LEN_KEY = 32;
    
    /**
     *   數字加密演算法
     **/
    public String encrypt(String str,long time){

        //數字校驗
        if(!isNumber(str)){
            System.out.println(str + "不是數字");
            
 
return null;
        }

        long number = Long.parseLong(str);
        long newNumber = (number + time) * SECRET_KEY;
        String[] numArr = String.valueOf(newNumber).split("");
        String[] initArr = CONVERT_KEY.split("");
        int len = numArr.length;
        StringBuffer buffer = new StringBuffer();

        //數字轉字母
        for(int i = 0; i < len; i++){
            int inx = Integer.parseInt(numArr[i]);
            buffer.append(initArr[inx]);
        }

        //隨機加入混淆字元
        String[] cwkArr = CONFUSED_WORDS_KEY.split("");
        if(len < LEN_KEY){
            int l = LEN_KEY - len;
            for(int i = 0; i < l; i++){
                int index = (int)(Math.random()*buffer.length());
                int inx = (int)(Math.random()*(CONFUSED_WORDS_KEY.length()));
                buffer.insert(index,cwkArr[inx]);
            }
        }
        String result = buffer.toString();
        System.out.println("加密字串：" + result);
        return result;
    }

    /**
     * 解密演算法
     * */
    public String decrypt(String str,long time){
        if(null == str || "".equals(str)){
            System.out.println("引數為空");
            return null;
        }
        int l = CONFUSED_WORDS_KEY.length();
        String[] cwkArr = CONFUSED_WORDS_KEY.split("");
        for(int i = 0; i < l; i++){
            str = str.replaceAll(cwkArr[i],"");
        }
        String[] initArr = str.split("");
        int len = initArr.length;
        StringBuffer result = new StringBuffer();
        for(int i = 0; i < len; i++ ){
            int k = CONVERT_KEY.indexOf(initArr[i]);
            if(k == -1){
                System.out.println("轉化失敗：" + str);
                return null;
            }
            result.append(k);
        }
        Long number;
        try {
            long total = Long.parseLong(result.toString());
            long sum = total/SECRET_KEY;
            number = sum - time;
            System.out.println("解密後數字：" + number);
        } catch (NumberFormatException e) {
            e.printStackTrace();
            return null;
        }
        return number.toString();
    }

    /**
     *   測試
     **/
    public static void main(String[] args) {
        long time = System.currentTimeMillis();
        System.out.println("time:" + time);
        Test t = new Test();
        String number = "15755141030";
        System.out.println(number);
        String result = t.encrypt(number,time);
        t.decrypt(result,time);
    }

    /**
     *  數字校驗
     * */
    public static boolean isNumber(String value) {
        String pattern = "^[0-9]*[1-9][0-9]*$";
        boolean isMatch = Pattern.matches(pattern, value);
        return isMatch;
    }
}

執行結果如下：

Connected to the target VM, address: '127.0.0.1:62962', transport: 'socket'
time:1544769549545
15755141030
加密字串：qFzzYFCMJYqCMgICDNxFeAqI#bJgIFDD
解密後數字：15755141030
Disconnected from the target VM, address: '127.0.0.1:62962', transport: 'socket'

Process finished with exit code 0

 總結：此加密演算法雖然簡單，但加密思想和加密原理值得學習，可以隨意修改數字祕鑰、轉換字元、混淆字母、總加密字串長度，並用於專案中。