package com.how2java.tmall.interceptor;
import java.util.Arrays;
import java.util.List;

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

import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

import com.how2java.tmall.pojo.Category;
import com.how2java.tmall.pojo.OrderItem;
import com.how2java.tmall.pojo.User;
import com.how2java.tmall.service.CategoryService;
import com.how2java.tmall.service.OrderItemService;
 
public class OtherInterceptor extends HandlerInterceptorAdapter {
    @Autowired
    CategoryService categoryService;
    @Autowired
    OrderItemService orderItemService;
     /**
     * 在业务处理器处理请求之前被调用
     * 如果返回false
     *     从当前的拦截器往回执行所有拦截器的afterCompletion(),再退出拦截器链
     * 如果返回true
     *    执行下一个拦截器,直到所有的拦截器都执行完毕
     *    再执行被拦截的Controller
     *    然后进入拦截器链,
     *    从最后一个拦截器往回执行所有的postHandle()
     *    接着再从最后一个拦截器往回执行所有的afterCompletion()
     */
    public boolean preHandle(HttpServletRequest request,
                             HttpServletResponse response, Object handler) throws Exception {
    	return true;

    }
 
    /**
     * 在业务处理器处理请求执行完成后,生成视图之前执行的动作
     * 可在modelAndView中加入数据，比如当前时间
     */

    public void postHandle(HttpServletRequest request,
            HttpServletResponse response, Object handler,    
            ModelAndView modelAndView) throws Exception {
    	/*这里是获取分类集合信息，用于放在搜索栏下面*/
        List<Category> cs = categoryService.list();
        request.getSession().setAttribute("cs", cs);

        /*这里是获取当前的contextPath:tmall_ssm,用与放在左上角那个变形金刚，点击之后才能够跳转到首页，否则点击之后也仅仅停留在当前页面*/
        HttpSession session = request.getSession();
        String contextPath=session.getServletContext().getContextPath();
        request.getSession().setAttribute("contextPath", contextPath);

        /*这里是获取购物车中一共有多少数量*/
        User user =(User)  session.getAttribute("user");
        int  cartTotalItemNumber = 0;
        if(null!=user) {
            List<OrderItem> ois = orderItemService.listByUser(user.getId());
            for (OrderItem oi : ois) {
            	cartTotalItemNumber+=oi.getNumber();
            }
       	
        }
        request.getSession().setAttribute("cartTotalItemNumber", cartTotalItemNumber);

    }
 
    /**  
     * 在DispatcherServlet完全处理完请求后被调用,可用于清理资源等   
     *   
     * 当有拦截器抛出异常时,会从当前拦截器往回执行所有的拦截器的afterCompletion()  
     */
     
    public void afterCompletion(HttpServletRequest request,    
            HttpServletResponse response, Object handler, Exception ex)  
    throws Exception {  
           
//        System.out.println("afterCompletion(), 在访问视图之后被调用");
    }  
       
} 

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">

    <!--启动注解识别-->
    <context:annotation-config/>

    <context:component-scan base-package="com.how2java.tmall.controller">
        <context:include-filter type="annotation"
                                expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>

    <mvc:annotation-driven />

    <!--开通静态资源的访问-->
    <mvc:default-servlet-handler />

    <!-- 视图定位 -->
    <bean
            class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass"
                  value="org.springframework.web.servlet.view.JstlView" />
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
    </bean>

    <!-- 对上传文件的解析-->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>
    <mvc:interceptors>
        <mvc:interceptor>
            <mvc:mapping path="/fore*"/>
            <bean class="com.how2java.tmall.interceptor.LoginInterceptor"/>
        </mvc:interceptor>
        <mvc:interceptor>
            <mvc:mapping path="/fore*"/>
            <bean class="com.how2java.tmall.interceptor.OtherInterceptor"/>
        </mvc:interceptor>
    </mvc:interceptors>
</beans>