spring boot 使用aop实现拦截器

实现功能：对某个目录下所有请求接口进行拦截判断，如检测登录状态等。

需要pom.xml引入aop:

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>

具体实现：

package com.tuijie.gainguest.common.aspect;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature;
//import com.tuijie.gainguest.common.enums.JsonCodeEnum;
//import com.tuijie.gainguest.common.result.JsonResp;
//import com.tuijie.gainguest.controller.Constants;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.HashMap;

/**
 * @Author: admin
 * @Description: 切面AOP
 * @Date Created in 9:39 AM 2020/3/31
 * @Modified By:
 */
@Aspect
@Component
@Slf4j //log日志，可选
public class SysPointcut {
    // 放行接口
    private final static String[] excludePathPatterns = {
            "/api/sysUserAdmin/login",
            "/api/sysUserAdmin/logout",
    };
    private static final SerializerFeature[] serializerFeatures;
    static {
        serializerFeatures = new SerializerFeature[] {
                SerializerFeature.WriteMapNullValue,
                SerializerFeature.WriteNullListAsEmpty
        };
    }

    /**
     * 后台管理切面AOP
     * 定义切入点，切入点为com.tuijie.gainguest.controller.admin包下所有类-接口
     * 通过@Pointcut注解声明频繁使用的切点表达式
     */
    @Pointcut("execution(* com.tuijie.gainguest.controller.admin..*.*(..)))")
    public void BrokerAspect() {}

    @Around("BrokerAspect()")
    public Object beforeExec(ProceedingJoinPoint pjp) throws Throwable {
        //获取request信息
        RequestAttributes ra = RequestContextHolder.getRequestAttributes();
        ServletRequestAttributes sra = (ServletRequestAttributes) ra;
        assert sra != null;
        HttpServletRequest request = sra.getRequest();
        HttpSession session = request.getSession();

        String uri = request.getRequestURI();
        if (!Arrays.asList(excludePathPatterns).contains(uri)) {
            Object admin = session.getAttribute(/*Constants.ACCOUNT_SESSION*/"test");
//            JsonResp jsonResp;
            if (admin == null) {
                log.warn("未登录: [{}] [{}]", session.getId(), uri);
//                jsonResp = JsonResp.fail(JsonCodeEnum.OVERTIME.getMessage(), JsonCodeEnum.OVERTIME.getCode());
                HttpServletResponse response = sra.getResponse();
                assert response != null;
                response.setCharacterEncoding("utf-8");
                response.setContentType("application/json; charset=UTF-8");
                PrintWriter writer = response.getWriter();
                writer.write(JSON.toJSONString(/*jsonResp*/new HashMap<String, Object>(){{put("id", 1);}}, serializerFeatures));
                writer.flush();
                writer.close();
                return null;
            }
        }

        return pjp.proceed();
    }

}