my-bigScreen/src/main/java/com/mini/mybigscreen/Config/LoginInterceptor.java

package com.mini.mybigscreen.Config;


import com.fasterxml.jackson.databind.ObjectMapper;
import com.mini.mybigscreen.Model.Result;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import jakarta.servlet.http.HttpSession;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.ObjectUtils;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

import java.io.PrintWriter;


@Component
public class LoginInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        ObjectMapper objectMapper = new ObjectMapper();
        HttpSession session = request.getSession(false);
        if (ObjectUtils.isEmpty(session)) {
            String json = objectMapper.writeValueAsString(Result.unauthorized());
            try (PrintWriter writer = response.getWriter()) {
                writer.write(json);
                writer.flush();
            }
            return false;
        }

        String token = (String) session.getAttribute("token");
        if (StringUtils.isEmpty(token)){
            String json = objectMapper.writeValueAsString(Result.unauthorized());
            try (PrintWriter writer = response.getWriter()) {
                writer.write(json);
                writer.flush();
            }
            return false;
        }

        return true;
    }
}