1.場(chǎng)景

web程序中刮萌，對(duì)用戶請(qǐng)求驮配，經(jīng)常會(huì)對(duì)請(qǐng)求進(jìn)行攔截處理，常用的處理方式如下：

• Filter
• Interceptor
• AOP

在此基于SpringBoot的web程序着茸，進(jìn)行這三種攔截方式的說明僧凤。

2.區(qū)別

三種攔截方式的區(qū)別如下：

3.請(qǐng)求順序

基于SpringBoot的web程序，F(xiàn)ilter擅羞、Interceptor尸变、Aop的請(qǐng)求順序如下：

Filter -> Interceptor ->AOP -> Controller

image-20210512172914548.png

4.版本

4.1 maven依賴

Filter和Interceptor有spring-boot-starter-web依賴即可：

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

AOP依賴的aspectJ需要額外的maven依賴：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-aop</artifactId>
    <version>2.2.9.RELEASE</version>
</dependency>

4.2 測(cè)試Controller

package com.wangcp.intercept.controller;

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

import java.util.HashMap;
import java.util.Map;

/**
* 測(cè)試類
* @author wangcp
* @date 2021/05/12 15:45
**/
@RestController
@RequestMapping(value = "/my")
public class MyController {

    @GetMapping(value = "/test")
    public Map<String,Object> test(String userName , String age){
        String message = "[Controller Action]：userName=" + userName + "；age=" + age;
        System.out.println(message);
        Map<String,Object> map = new HashMap<>();
        map.put("success",true);
        map.put("message",message);
        return map;
    }

}

5.Filter代碼實(shí)現(xiàn)

5.1 說明

1.實(shí)現(xiàn)接口

實(shí)現(xiàn)接口：javax.servlet.Filter

2.核心方法

public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {}

5.2 定義

1.定義Filter

package com.wangcp.intercept.filter;


import javax.servlet.*;
import java.io.IOException;
import java.util.Date;

/**
* 計(jì)算執(zhí)行時(shí)間Filter
* @author wangcp
* @date 2021/05/12 15:50
**/
public class TimerFilter implements Filter {

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        long begin = new Date().getTime();
        System.out.println("[Filter-Time]：進(jìn)入Filter");
        // 執(zhí)行servlet方法（如攔截請(qǐng)求减俏，不執(zhí)行servlet召烂，可不執(zhí)行此方法）
        filterChain.doFilter(servletRequest , servletResponse);
        long end = new Date().getTime();
        System.out.println("[Filter-Time]：結(jié)束Filter，共" + (end - begin) + "毫秒");
    }
}

2.配置

package com.wangcp.intercept.filter.config;

import com.wangcp.intercept.filter.TimerFilter;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.Arrays;

/**
* filter配置類
* @author wangcp
* @date 2021/05/12 15:54
**/
@Configuration
public class WebFilterConfig {

    @Bean
    public FilterRegistrationBean timerFilter(){
        FilterRegistrationBean registrationBean = new FilterRegistrationBean();
        // 設(shè)置：實(shí)現(xiàn)類
        registrationBean.setFilter(new TimerFilter());
        // 設(shè)置：UrlPatterns (要攔截的url)
        registrationBean.setUrlPatterns(Arrays.asList("/*"));
        // 設(shè)置：優(yōu)先級(jí)
        registrationBean.setOrder(1);
        return registrationBean;
    }

}

5.3 測(cè)試

1.測(cè)試請(qǐng)求

http://localhost:8080/my/test?userName=wangcp&age=18

2.輸出結(jié)果

[Filter-Time]：進(jìn)入Filter
[Controller Action]：userName=wangcp娃承；age=18
[Filter-Time]：結(jié)束Filter奏夫，共40毫秒

5.4 配置順序

// 設(shè)置：優(yōu)先級(jí)
registrationBean.setOrder(1);

6.HandlerInterceptor 代碼實(shí)現(xiàn)

6.1 說明

1.實(shí)現(xiàn)接口

實(shí)現(xiàn)接口：org.springframework.web.servlet.HandlerInterceptor

2.核心方法

各方法詳細(xì)介紹可查看： https://blog.csdn.net/weixin_41767154/article/details/84648873

// 調(diào)用Controller方法之前
boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception;

// 在當(dāng)前這個(gè)Interceptor的preHandle方法返回值為true的時(shí)候才會(huì)執(zhí)行
void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,@Nullable ModelAndView modelAndView) throws Exception;

// 也是需要當(dāng)前對(duì)應(yīng)的Interceptor的preHandle方法的返回值為true時(shí)才會(huì)執(zhí)行
void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler,@Nullable Exception ex) throws Exception;

6.2 定義

1.定義Interceptor

package com.wangcp.intercept.interceptor;

import com.alibaba.fastjson.JSONObject;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.PrintWriter;

/**
* 鑒權(quán)攔截器
* @author wangcp
* @date 2021/05/12 16:05
 * https://blog.csdn.net/weixin_41767154/article/details/84648873
**/
@Component
public class AuthInterceptor implements HandlerInterceptor {

    /**
    * 調(diào)用Controller方法之前
    * @author wangcp
    * @date 2021/05/12 16:06
     * @param request
     * @param response
     * @param handler
    * @return boolean
    */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("[Interceptor-auth]：進(jìn)入preHandle");
        if(handler instanceof HandlerMethod){
            HandlerMethod handlerMethod = (HandlerMethod) handler;
            System.out.println("[Interceptor-auth]：訪問信息=" + handlerMethod.getShortLogMessage());
            // 獲取head鑒權(quán)信息
            String sign = request.getHeader("sign");
            if (!"123456".equals(sign)) {
                // 鑒權(quán)不通過
                response.setCharacterEncoding("utf-8");
                response.setContentType("application/json; charset=utf-8");
                PrintWriter writer = response.getWriter();
                JSONObject jsonObject = new JSONObject();
                jsonObject.put("success", false);
                jsonObject.put("message", "鑒權(quán)失敗");
                writer.write(jsonObject.toJSONString());
                writer.flush();
                writer.close();
                System.out.println("[Interceptor-auth]：----------鑒權(quán)不通過----------");
                System.out.println("[Interceptor-auth]：結(jié)束preHandle");
                return false;
            } else {
                // 鑒權(quán)通過
                System.out.println("[Interceptor-auth]：----------鑒權(quán)通過----------");
                System.out.println("[Interceptor-auth]：結(jié)束preHandle");
                return true;
            }
        }
        System.out.println("[Interceptor-auth]：結(jié)束preHandle");
        // 返回true為通過校驗(yàn)，返回false為不通過校驗(yàn)
        return true;
    }

    /**
    * 在當(dāng)前這個(gè)Interceptor的preHandle方法返回值為true的時(shí)候才會(huì)執(zhí)行
     * 執(zhí)行時(shí)機(jī)：在DispatcherServlet進(jìn)行視圖的渲染之前執(zhí)行历筝，也就是說在這個(gè)方法中你可以對(duì)ModelAndView進(jìn)行操作
    * @author wangcp
    * @date 2021/05/12 16:07
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
    * @return void
    */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("[Interceptor-auth]：postHandle ModelAndView=" + JSONObject.toJSONString(modelAndView));
    }

    /**
     * 也是需要當(dāng)前對(duì)應(yīng)的Interceptor的preHandle方法的返回值為true時(shí)才會(huì)執(zhí)行
     * 執(zhí)行時(shí)機(jī)：該方法將在整個(gè)請(qǐng)求完成之后酗昼，也就是DispatcherServlet渲染了視圖執(zhí)行
     * （這個(gè)方法的主要作用是用于清理資源的）
    * @author wangcp
    * @date 2021/05/12 16:07
     * @param request
     * @param response
     * @param handler
     * @param ex
    * @return void
    */
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("[Interceptor-auth]：afterCompletion Exception=" + JSONObject.toJSONString(ex));
    }
}

2.配置

package com.wangcp.intercept.interceptor.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
* WEB統(tǒng)一配置
* @author wangcp
* @date 2021/05/12 16:20
**/
@Component
public class GlobalWebMvcConfigurer implements WebMvcConfigurer {

    @Autowired
    private HandlerInterceptor authInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(authInterceptor).addPathPatterns("/**");

        // 支持定義多個(gè)PathPattern和excludePathPatterns
//        registry.addInterceptor(authInterceptor).addPathPatterns("/xxx","/**").excludePathPatterns("/yyy","/zzz");
    }
}

6.3 測(cè)試

1.正向測(cè)試

請(qǐng)求：

http://localhost:8080/my/test?userName=wangcp&age=18
請(qǐng)求head：sign=123456

輸出結(jié)果：

[Interceptor-auth]：進(jìn)入preHandle
[Interceptor-auth]：訪問信息=com.wangcp.intercept.controller.MyController#test[2 args]
[Interceptor-auth]：----------鑒權(quán)通過----------
[Interceptor-auth]：結(jié)束preHandle
[Controller Action]：userName=wangcp；age=18
[Interceptor-auth]：postHandle ModelAndView=null
[Interceptor-auth]：afterCompletion Exception=null

請(qǐng)求結(jié)果：

{
    "success": true,
    "message": "[Controller Action]：userName=wangcp梳猪；age=18"
}

2.逆向測(cè)試

請(qǐng)求：

http://localhost:8080/my/test?userName=wangcp&age=18
請(qǐng)求head：sign=8888

輸出結(jié)果：

[Interceptor-auth]：進(jìn)入preHandle
[Interceptor-auth]：訪問信息=com.wangcp.intercept.controller.MyController#test[2 args]
[Interceptor-auth]：----------鑒權(quán)不通過----------
[Interceptor-auth]：結(jié)束preHandle

請(qǐng)求結(jié)果：

{
    "success": false,
    "message": "鑒權(quán)失敗"
}

7.AOP代碼實(shí)現(xiàn)

7.1 說明

相關(guān)注解

各注解詳細(xì)介紹可參考：https://blog.csdn.net/qq_45515432/article/details/104187326

org.aspectj.lang.annotation.Aspect
org.aspectj.lang.annotation.Pointcut
org.aspectj.lang.annotation.Before
org.aspectj.lang.annotation.After
org.aspectj.lang.annotation.Around

7.2 定義

package com.wangcp.intercept.aop;

import com.alibaba.fastjson.JSONObject;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;

/**
* AOP實(shí)現(xiàn)攔截請(qǐng)求
* @author wangcp
* @date 2021/05/12 16:34
 * https://blog.csdn.net/qq_45515432/article/details/104187326
**/
@Component
@Order(1)
@Aspect
public class LogApp {

    @Pointcut("execution(public * com.wangcp..controller..*(..))")
    public void log() {
        
    }

    @Before("log()")
    public void doBefore(JoinPoint joinPoint) {
        System.out.println("[AOP-log]：Before");
    }

    @After("log()")
    public void doAfter(JoinPoint joinPoint) {
        System.out.println("[AOP-log]：After");
    }

    @Around("log()")
    public Object doAround(ProceedingJoinPoint joinPoint) throws Throwable {
        System.out.println("[AOP-log]：Around-進(jìn)入");
        // 請(qǐng)求參數(shù)
        System.out.println("[AOP-log]：Around-請(qǐng)求參數(shù)="+ JSONObject.toJSONString(joinPoint.getArgs()));

        // 執(zhí)行切面方法
        Object object = joinPoint.proceed();

        // 執(zhí)行結(jié)果
        System.out.println("[AOP-log]：Around-執(zhí)行結(jié)果="+ JSONObject.toJSONString(object));
        System.out.println("[AOP-log]：Around-結(jié)束");
        return object;
    }
}

7.3 測(cè)試

1.測(cè)試請(qǐng)求

http://localhost:8080/my/test?userName=wangcp&age=18

2.輸出結(jié)果

[AOP-log]：Around-進(jìn)入
[AOP-log]：Around-請(qǐng)求參數(shù)=["wangcp","18"]
[AOP-log]：Before
[Controller Action]：userName=wangcp麻削；age=18
[AOP-log]：After
[AOP-log]：Around-執(zhí)行結(jié)果={"success":true,"message":"[Controller Action]：userName=wangcp；age=18"}
[AOP-log]：Around-結(jié)束

3.請(qǐng)求結(jié)果

{"success":true,"message":"[Controller Action]：userName=wangcp春弥；age=18"}

8.匯總測(cè)試

同時(shí)打開上述的Filter呛哟，Interceptor，AOP匿沛，一起來攔截請(qǐng)求扫责。

1.測(cè)試請(qǐng)求

http://localhost:8080/my/test?userName=wangcp&age=18
請(qǐng)求head：sign=123456

2.輸出結(jié)果

[Filter-Time]：進(jìn)入Filter
[Interceptor-auth]：進(jìn)入preHandle
[Interceptor-auth]：訪問信息=com.wangcp.intercept.controller.MyController#test[2 args]
[Interceptor-auth]：----------鑒權(quán)通過----------
[Interceptor-auth]：結(jié)束preHandle
[AOP-log]：Around-進(jìn)入
[AOP-log]：Around-請(qǐng)求參數(shù)=["wangcp","18"]
[AOP-log]：Before
[Controller Action]：userName=wangcp；age=18
[AOP-log]：After
[AOP-log]：Around-執(zhí)行結(jié)果={"success":true,"message":"[Controller Action]：userName=wangcp俺祠；age=18"}
[AOP-log]：Around-結(jié)束
[Interceptor-auth]：postHandle ModelAndView=null
[Interceptor-auth]：afterCompletion Exception=null
[Filter-Time]：結(jié)束Filter公给，共1毫秒

輸出順序與文章開頭請(qǐng)求順序講解一致。

3.請(qǐng)求結(jié)果

{
    "success": true,
    "message": "[Controller Action]：userName=wangcp蜘渣；age=18"
}