1.在写拦截器的时候获取 通过HandlerMethod handlerMethod=(HandlerMethod)object 获取请求方法，然后判断是否为请求接口方法的时候出错

先贴出拦截器代码，我是一个初级菜鸡，此代码来自于网络其他博客仿写和修改，具体有些不记得出处了，原博客应该没有错误，是自己太粗心导致的错误😂。

package com.zhou.bjgl.bjgl.Interceptor;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.zhou.bjgl.bjgl.exception.BwException;
import com.zhou.bjgl.bjgl.exception.BwExceptionEnum;
import com.zhou.bjgl.bjgl.myAnnotations.UserLoginToken;
import com.zhou.bjgl.bjgl.req.UserReq;
import com.zhou.bjgl.bjgl.resp.user.BUserForInfoResp;
import com.zhou.bjgl.bjgl.resp.user.BUserForQueryResp;
import com.zhou.bjgl.bjgl.service.CommonService;

import org.springframework.messaging.handler.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;

/**
 * @ClassName: AuthenticationInterceptor
 * @Description:
 * @Author: zhou
 * @Date: 2022/2/25 14:08
 */
public class AuthenticationInterceptor implements HandlerInterceptor {

    @Resource
    private CommonService commonService;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object object)
            throws Exception {

        String token = request.getHeader("x-token");

        // 如果不是映射到方法直接通过
        if(!(object instanceof HandlerMethod)){
            return true;
        }
        HandlerMethod handlerMethod=(HandlerMethod)object;
        Method method = handlerMethod.getMethod();



        //检查有没有需要用户权限的注解 @UserLoginToken
        if(method.isAnnotationPresent(UserLoginToken.class)){
            UserLoginToken userLoginToken = method.getAnnotation(UserLoginToken.class);
            if(userLoginToken.required()){
                //开始认证
                if(token==null){
                    throw new BwException(BwExceptionEnum.NO_TOKEN);
                }
                //拿到token中的userId
                String userId;
                try {
                    userId = JWT.decode(token).getAudience().get(0);
                } catch (Exception e) {
                    throw new RuntimeException("401");
                }

                UserReq userReq = new UserReq();
                userReq.setUsername(userId);
                BUserForInfoResp user = commonService.getUserInfo(userReq);

                if(user==null){
                    throw new BwException(BwExceptionEnum.USER_NOT_EXIST);
                }

                //验证token
                JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(user.getPassword())).build();
                try {
                    jwtVerifier.verify(token);
                } catch (Exception e) {
                    throw new RuntimeException("401");
                }

                return true;
            }

        }

        return true;
    }
}

有没有发现哪里出错了，没错就是HandlerMethod的包导入错误了。

正确的包应该是：

import org.springframework.web.method.HandlerMethod;

关于另一个包的同名类，我目前还不知道具体作用是什么。