目录结构

pom.xml

<dependency>
      <groupId>javax.xml.bind</groupId>
      <artifactId>jaxb-api</artifactId>
      <version>2.3.1</version>
</dependency>
<dependency>
      <groupId>io.jsonwebtoken</groupId>
      <artifactId>jjwt</artifactId>
      <version>0.9.1</version>
</dependency>

utils/JwtTokenUtil

package com.example.demo.utils;

import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import java.util.Date;

public class JwtTokenUtil {
    private static final long nowMillis = System.currentTimeMillis();
    private static final long expMillis = nowMillis + (60 * 1000);  //有效期30天
    private static final Date exp = new Date(expMillis);
    private static final String SECRET_KEY = "your_secret_key";
    public static String generateToken(String username, String password) {
        return Jwts.builder()
                .setSubject(username) // 代表这个JWT的主体，即它的所有人
                .claim("password", password)  // 记录一些不重要的对象信息放到claims
                .setExpiration(exp) //设置有效期
                .setIssuedAt(new Date()) // 一个时间戳，代表这个JWT的签发时间
                .signWith(SignatureAlgorithm.HS256, SECRET_KEY)  //签名方式
                .compact();
    }
    public static boolean validateToken(String token, String uname) {
        if (token==null){
            return false;
        }
        System.out.println("有效时间:");
        System.out.println(exp);
        try {
            String username = Jwts.parser()
                    .setSigningKey(SECRET_KEY)
                    .parseClaimsJws(token)
                    .getBody()
                    .getSubject();
            return username.equals(uname) && !isTokenExpired(token);
        } catch (Exception e) {
            return false;
        }
    }

    private static boolean isTokenExpired(String token) {
        return Jwts.parser()
            .setSigningKey(SECRET_KEY)
            .parseClaimsJws(token)
            .getBody()
            .getExpiration()
            .before(new Date());
    }
}

controller/Login

package com.example.demo.controller;

import com.example.demo.utils.JwtTokenUtil;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class Login {
    @GetMapping("/login")
    public String login() {
        String token = JwtTokenUtil.generateToken("username", "password");
        System.out.println("token:" + token);
        String password = "password123";
        String storedMD5 = "482c811da5d5b4bc6d497ffa98491e38"; // 假设这是数据库中存储的MD5密码散列
        // 验证密码
        boolean isValid = MD5Checker.checkPassword(password, storedMD5);
        System.out.println("Password is valid: " + isValid);
        return token;
    }

    @GetMapping("/vertical")
    public Boolean vertical(@RequestParam String token) {
        Boolean validStatus = JwtTokenUtil.validateToken(token, "username");
        System.out.println(validStatus);
        return validStatus;
    }
}

utils/MD5Checker

package com.example.demo.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class MD5Checker {

    public static String toMD5(String originalString) {
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(originalString.getBytes());
            byte[] digest = md.digest();
            StringBuilder sb = new StringBuilder();
            for (byte b : digest) {
                sb.append(String.format("%02x", b));
            }
            return sb.toString();
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("Could not find MD5 algorithm", e);
        }
    }

    public static boolean checkPassword(String inputPassword, String storedMD5) {
        String md5 = toMD5(inputPassword);
        return md5.equalsIgnoreCase(storedMD5);
    }
}