Spring MVC学习07拦截器

自定义拦截器：

package com.yas.interceptor;

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

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

public class MyInterceptor implements HandlerInterceptor {
    //在handler之前执行
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
//        System.out.println("preHandle");
        HttpSession session = request.getSession();
        if(session.getAttribute("state")!=null){
            return true;
        }
        response.sendRedirect("/login.jsp");
        return false;
    }

    //在handler之后，响应之前执行
    //改动请求中的数据
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
//        System.out.println("postHandle");
    }

    //在视图渲染完毕之后执行
    //资源回收
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
//        System.out.println("afterCompletion");
    }
}

定义Controller：

package com.yas.controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.SessionAttributes;

@Controller
@RequestMapping("/inter")
@SessionAttributes("state")
public class InterceptorController {

    @RequestMapping("/login")
    public String login(Model model){
        model.addAttribute("state","ok");
        return "main";
    }

    @RequestMapping("/test1")
    public String test1(){
        return "main";
    }

    @RequestMapping("/test2")
    public String test2(){
        return "main";
    }
}

在mvc.xml进行配置：

<mvc:interceptors>
        <mvc:interceptor>
<!--            <mvc:mapping path="/inter/test1"/>-->
<!--            <mvc:mapping path="/inter/test2"/>-->
            <mvc:mapping path="/inter/**"/>
            <mvc:exclude-mapping path="/inter/login"/>
            <bean class="com.yas.interceptor.MyInterceptor"></bean>
        </mvc:interceptor>
    </mvc:interceptors>