架构师训练营 -week11 命题作业

package com.jeff.kafka.utils;
import java.security.MessageDigest;
/**
 * @Description TODO
 * @Date 2020/8/24 10:05 上午
 * @Author jeff.sheng
 */
public class EncryUtils {
    /**
     * 将字节数组转为16进制字符串
     * @param arr
     * @return
     */
    private static String hex(byte[] arr) {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < arr.length; ++i) {
            sb.append(Integer.toHexString((arr[i] & 0xFF) | 0x100).substring(1, 3));
        }
        return sb.toString();
    }
    /**
     * 进程md5加密并转为16进制字符串
     * @param str
     * @return
     */
    private static String md5Hex(String str) {
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] digest = md.digest(str.getBytes());
            return hex(digest);
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e.toString());
            return "";
        }
    }
    public static  boolean checkPWD(String userID,String pwdPlaintext,String pwdCiphertext){
        String pwd = getSaltMD5(userID,pwdPlaintext);
        return pwdCiphertext.equals(pwd);
    }
    public static String getSaltMD5(String salt, String password) {
        password = md5Hex(password + salt);
        return password;
    }
    public static void main(String[] args) {
        //指定salt为jeffSheng对密码明文123456进行加密
        System.out.println(getSaltMD5("jeffSheng","123456"));
        //true 当salt为jeffSheng时看到结果为true，因为加密salt是一致的
        System.out.println(checkPWD("jeffSheng","123456","c9ef20dd8652713e46dbf9bb6e0c9d56"));
        //false 当salt不是jeffSheng时结果为false，因为加密salt不一致
        System.out.println(checkPWD("jeffSmile","123456","c9ef20dd8652713e46dbf9bb6e0c9d56"));
    }
}