[springmvc]拦截器功能

11.拦截器

• 只会拦截controller的请求，对于静态资源不处理

被spring代理的拦截器实现只需要两步：

1.实现一个拦截器类

package com.spring.config;

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

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

/**
 * @author panglili
 * @create 2022-07-26-13:43
 */
//继承一个拦截器
public class MyInterceptor implements HandlerInterceptor {

    //true 放行
    //false 不放行
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("处理前-------------");
        return true;
    }

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

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

        System.out.println("清理—--------------");
    }
}

2.配置拦截器

<!--拦截器配置-->
<mvc:interceptors>
    <mvc:interceptor>
        <mvc:mapping path="/**"/>
        <bean class="com.spring.config.MyInterceptor"/>
    </mvc:interceptor>
</mvc:interceptors>