<dependency>
    <groupId>com.auth0</groupId>
    <artifactId>java-jwt</artifactId>
    <version>3.19.0</version>
</dependency>

public class JwtUtils {
    /** 過期時間，單位：秒，默認(rèn)半小時過期 **/
    private static final long EXPIRATION = 60 * 30L;
    /** 密鑰，一般長度較長，內(nèi)容較復(fù)雜 **/
    private static final String SECRET = "my_secret";
    /**
     * @description 創(chuàng)建token
     * @author xBaozi
     * @date 20:49 2022/3/31
     **/
    public static String createToken(Map<String, String> claimMap) {
        // 當(dāng)前時間戳加上設(shè)定的毫秒數(shù)（1秒 == 1000毫秒）
        Date expiration = new Date(System.currentTimeMillis() + EXPIRATION * 1000);
        // 設(shè)置JWT頭部
        Map<String, Object> map = new HashMap<>();
        map.put("alg", "HS256");
        map.put("typ", "JWT");
        // 創(chuàng)建token
        JWTCreator.Builder builder = JWT.create();
        //使用Lambda創(chuàng)建payload
        claimMap.forEach((k,v)->{
            builder.withClaim(k,v);
        });
        // 添加頭部，可省略保持默認(rèn)，默認(rèn)即map中的鍵值對
        return builder.withHeader(map)
                // 設(shè)置過期時間
                .withExpiresAt(expiration)
                // 設(shè)置簽名解碼算法
                .sign(Algorithm.HMAC256(SECRET));
    }
    /**
     * @description 驗證token
     * @author xBaozi
     * @date 23:36 2022/3/31
     **/
    public static DecodedJWT verifyToken(String token) {
        return JWT.require(Algorithm.HMAC256(SECRET)).build().verify(token);
    }
}

public class JwtInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        Map<String, Object> map = new HashMap<>();
        //獲取請求頭中令牌
        String token = request.getHeader("token");
        try {
            //驗證令牌
            JwtUtils.verifyToken(token);
            //驗證成功，放行請求
            return true;
        } catch (SignatureVerificationException e) {
            e.printStackTrace();
            map.put("msg", "無效簽名!");
        } catch (TokenExpiredException e) {
            e.printStackTrace();
            map.put("msg", "token過期!");
        } catch (AlgorithmMismatchException e) {
            e.printStackTrace();
            map.put("msg", "token算法不一致!");
        } catch (Exception e) {
            e.printStackTrace();
            map.put("msg", "token無效!!");
        }
        //設(shè)置狀態(tài)
        map.put("state", false);
        //將map轉(zhuǎn)為json
        String json = new ObjectMapper().writeValueAsString(map);
        // 相應(yīng)json數(shù)據(jù)
        response.setContentType("application/json;charset=UTF-8");
        response.getWriter().println(json);
        return false;
    }
}

@Configuration
public class JwtConfig implements WebMvcConfigurer{
        @Override
        public void addInterceptors(InterceptorRegistry registry) {
            registry.addInterceptor(new JwtInterceptor())
                    //添加攔截路徑
                    .addPathPatterns("/**")
                    //添加放行路徑
                    .excludePathPatterns("/user/login");
        }
}

@RestController
@RequestMapping("/user")
@Slf4j
public class UserController {
    // 這里只做演示，就不寫Service層了
    // @Autowired
    // private UserService userService;
    /**
     * @description 登錄功能
     * @author xBaozi
     * @date 0:02 2022/4/1
     * @param user  user對象，默認(rèn)有值
     **/
    @GetMapping("/login")
    public Map<String,Object> login(User user){
        log.info("用戶名: [{}]",user.getName());
        log.info("密碼: [{}]",user.getPassword());
        Map<String, Object> map = new HashMap<>();
        try{
            Map<String,String> payload =  new HashMap<>();
            payload.put("id",user.getId());
            payload.put("name",user.getName());
            // 生成JWT的令牌
            String token = JwtUtils.createToken(payload);
            map.put("state",true);
            map.put("msg","認(rèn)證成功");
            // 響應(yīng)token
            map.put("token",token);
        }catch (Exception e){
            map.put("state",false);
            map.put("msg",e.getMessage());
        }
        return map;
    }
    @PostMapping("/other")
    public Map<String,Object> test(HttpServletRequest request){
        Map<String, Object> map = new HashMap<>();
        //處理自己業(yè)務(wù)邏輯
        String token = request.getHeader("token");
        DecodedJWT verify = JwtUtils.verifyToken(token);
        log.info("用戶id: [{}]",verify.getClaim("id").asString());
        log.info("用戶name: [{}]",verify.getClaim("name").asString());
        map.put("state",true);
        map.put("msg","請求成功!");
        return map;
    }
}