Java后端进行Base64码加密、解密及MD5加密

Base64码加密、解密：

package com.shuixian.jianghao.utils;

import java.io.UnsupportedEncodingException;
import java.util.Base64;

/**
 *  base64码加密工具类，主要用于从数据库查询出用户名和密码后，进行加密然后传给SIEM平台
 * */
public class Base64Util {
    private static final char last2byte = (char) Integer.parseInt("00000011", 2);
    private static final char last4byte = (char) Integer.parseInt("00001111", 2);
    private static final char last6byte = (char) Integer.parseInt("00111111", 2);
    private static final char lead6byte = (char) Integer.parseInt("11111100", 2);
    private static final char lead4byte = (char) Integer.parseInt("11110000", 2);
    private static final char lead2byte = (char) Integer.parseInt("11000000", 2);
    private static final char[] encodeTable = new char[]{'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};

    public Base64Util() {
    }

    /** 对明文进行base64码加密
     * @param from 需要加密的明文的byte[]数组
     * @return 加密之后的base64码
     * */
    public static String encode(byte[] from) {
        StringBuilder to = new StringBuilder((int) ((double) from.length * 1.34D) + 3);
        int num = 0;
        char currentByte = 0;

        int i;
        for (i = 0; i < from.length; ++i) {
            for (num %= 8; num < 8; num += 6) {
                switch (num) {
                    case 0:
                        currentByte = (char) (from[i] & lead6byte);
                        currentByte = (char) (currentByte >>> 2);
                    case 1:
                    case 3:
                    case 5:
                    default:
                        break;
                    case 2:
                        currentByte = (char) (from[i] & last6byte);
                        break;
                    case 4:
                        currentByte = (char) (from[i] & last4byte);
                        currentByte = (char) (currentByte << 2);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead2byte) >>> 6);
                        }
                        break;
                    case 6:
                        currentByte = (char) (from[i] & last2byte);
                        currentByte = (char) (currentByte << 4);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead4byte) >>> 4);
                        }
                }

                to.append(encodeTable[currentByte]);
            }
        }

        if (to.length() % 4 != 0) {
            for (i = 4 - to.length() % 4; i > 0; --i) {
                to.append("=");
            }
        }

        return to.toString();
    }

    /** 对base64码进行解码
     * @param code 需要解码的base64字符串
     * @return 解码之后的字符串
     * */
    public static String decode(String code){
        String str="";
        try {
            str=new String(Base64.getDecoder().decode(code),"utf-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return str;
    }
}

MD5加密：

package com.shuixian.jianghao.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Random;
import java.util.UUID;

/** 生成token令牌的工具类
 * @author 王子洋
 * @date 2019-04-18
 * */
public class TokenUtil {
    /** 生成token
     * @param userId 用户ID
     * @return 加密之后的token
     * */
    public static String getToken(String userId){
        String token= System.currentTimeMillis()+userId.substring(0,2)+ new Random().nextInt(666)+userId;
        String result="";
        try {
            MessageDigest md=MessageDigest.getInstance("md5");
            result=Base64Util.encode(md.digest(token.getBytes()));
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return result;
    }
}