【SpringMVC】11 拦截器

拦截器是AOP具体的应用

只能使用SpringMVC自己的组件有效

之拦截访问控制器方法的请求，

如果访问的是jsp、html、css、img、js这一类的静态资源，则不会拦截

---

演示：

编写一个拦截器的测试，控制器的方法

package cn.dai.controller;

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

/**
 * @author ArkD42
 * @file SpringMVC
 * @create 2020 - 05 - 07 - 19:39
 */

@RestController
public class TestController {

    @GetMapping("/visit")
    public String test(){
        System.out.println("The TestController.test() has bean browsed !!!");
        return "browsed access!!!";
    }
}

编写拦截器实现类，实现拦截方法

package cn.dai.interceptor;

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

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * @author ArkD42
 * @file SpringMVC
 * @create 2020 - 05 - 07 - 19:35
 */

public class SpringMvcInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("- - - - 拦截前 - - - -");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("- - - - 处理后 - - - -");
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("- - - - 清理 - - - -");
    }
}

注册到SpringMVC中

    <!-- 拦截器 -->
    <mvc:interceptors>

        <mvc:interceptor>
            <!-- /** 表示所有的请求，/*只表示当前一个路由的情况下实现 -->
            <mvc:mapping path="/**"/>

            <!-- 具体是哪个类来完成的 -->
            <bean class="cn.dai.interceptor.SpringMvcInterceptor" />
        </mvc:interceptor>

    </mvc:interceptors>

访问结果

---