<dependency>
    <groupId>com.auth0</groupId>
    <artifactId>java-jwt</artifactId>
    <version>4.3.0</version>
</dependency>

@Test
//生成token
void jwtdemo01(){
     Calendar instance = Calendar.getInstance();
     //instance.add(Calendar.SECOND, 90);
     instance.add(Calendar.DAY_OF_WEEK, 7);
    System.out.println(instance.getTime());
    String token = JWT.create()
            .withClaim("username", "李四")//payload 设置自定义用户名
            .withExpiresAt(instance.getTime())//设置过期时间
            .sign(Algorithm.HMAC256("123"));//设置签名 密钥
    System.out.println(token);
    //"eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJleHAiOjE3MDM5NDcyODMsInVzZXJuYW1lIjoi5p2O5ZubIn0.3onRy8p0G9ojnpA9u5h5ytd8hLZpGMZUyj49LTge5ao"
}
@Test
//验证token
void jwtdemo02(){
    //创建验证对象
    //参数1：签名使用的算法 参数2：签名的密钥
    JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256("123")).build();
    //
    DecodedJWT verify =jwtVerifier.verify("eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJleHAiOjE3MDM5NDcyODMsInVzZXJuYW1lIjoi5p2O5ZubIn0.3onRy8p0G9ojnpA9u5h5ytd8hLZpGMZUyj49LTge5ao");
    System.out.println(verify.getClaim("username"));
}

public class JWTUtil {
    private static final   String TOKENKey="qgs12345";
    /**
     * 生成token
     * @param map
     * @return 返回token
     */
    public static String getToken(Map<String,String> map){
        Calendar instance = Calendar.getInstance();
        instance.add(Calendar.DATE,7);//7天过期
        //添加payload
        JWTCreator.Builder builder = JWT.create();
        map.forEach((k,v)->{
            builder.withClaim(k,v);
        });
        builder.withExpiresAt(instance.getTime());//设置令牌过期时间
        //生成并返回token
       return builder.sign(Algorithm.HMAC256(TOKENKey)).toString();
    }
    /**
     * 验证token
     * @param token
     */
    public static void verify(String token){
        JWT.require(Algorithm.HMAC256(TOKENKey)).build().verify(token);
    }
    /**
     * 获取token中payload
     * @param token
     * @return
     */
    public static DecodedJWT getTokenInfo(String token){
        return JWT.require(Algorithm.HMAC256(TOKENKey)).build().verify(token);
    }
}

@RestController
@RequestMapping("/users")
@CrossOrigin //表示都允许跨域访问
public class UserController extends BaseController{
    @Autowired
    private UserService userModuleService;
    @RequestMapping("/login")
    public Map<String,Object> login(String username, String password){
        Map<String,Object> map =new HashMap<>();
        try {
            User data = userModuleService.login(username, password);
            Map<String,String> payload =new HashMap<>();
            payload.put("username",data.getUsername());
            //生成JWT令牌
            String token =JWTUtil.getToken(payload);
            map.put("state",true);
            map.put("msg","登入成功");
            map.put("token",token);
        }catch (Exception e){
            map.put("state",false);
            map.put("msg","登入失败");
        }
        return map;
    }
    //验证token
    @RequestMapping("/loginVerify")
    public Map<String,Object> loginVerify(String token){
        System.out.println(token);
        Map<String,Object> map =new HashMap<>();
        try {
            //生成JWT令牌
            JWTUtil.verify(token);
            map.put("state",true);
            map.put("msg","验证成功");
        }catch (Exception e){
            map.put("state",true);
            map.put("msg","验证失败");
        }
        return map;
    }
}