springboot实现拦截器

1、创建springboot项目

    4.0.0
    
        org.springframework.boot
        spring-boot-starter-parent
        2.1.1.RELEASE
         
    
    com.example
    demo
    0.0.1-SNAPSHOT
    jar
    demo
    Demo project for Spring Boot

    
        1.8
    

    
        
            org.springframework.boot
            spring-boot-starter
        

        
            org.springframework.boot
            spring-boot-starter-web
        


        
            org.springframework.boot
            spring-boot-starter-test
            test
        
        
            org.springframework.boot
            spring-boot-starter-aop
        
        
            net.sf.json-lib
            json-lib
            2.4
            jdk15
        
    

 

2、自定义拦截器：

package com.example.demo.intercepter;

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Component
public class AIntercepter implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("A-----------A");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}

package com.example.demo.intercepter;

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Component
public class MyIntercepter implements HandlerInterceptor {
    /**
     * 进入handler之前
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("进入handler之前");
        return true;
    }

    /**
     * 进入handler之后，返回model之前
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    /**
     * 返回model之后
     * @param request
     * @param response
     * @param handler
     * @param ex
     * @throws Exception
     */
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}

3、配置：

package com.example.demo.config;

import com.example.demo.intercepter.AIntercepter;
import com.example.demo.intercepter.MyIntercepter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringBootConfiguration;
import org.springframework.boot.autoconfigure.web.servlet.WebMvcAutoConfiguration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
@SpringBootConfiguration
public class MySpringMVCConfig extends WebMvcConfigurerAdapter {
    @Autowired
    private MyIntercepter myIntercepter;
    @Autowired
    private AIntercepter aIntercepter;
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(myIntercepter).addPathPatterns("/**");
        registry.addInterceptor(aIntercepter).addPathPatterns("/**");
    }
}

4、目标：
 

package com.example.demo.controller;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class SampleController {
    @RequestMapping("/home")
    public String home() {
        return "Hello World!";
    }
}