HandlerInterceptor：没有调用Interceptor

Question

I am implementing a MyInterceptor.java class which extends HandlerInterceptor implementing preHandle() , postHandle() and afterCompletion() . The interceptor methods are not being called.

Here is MyInterceptor.java

    package com.mykong.common.interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

public class MyInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {
        System.out.println("Pre-handle");

        return true;
    }

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

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

}

Here is mvc-dispatcher-servlet.xml

    <beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    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-3.0.xsd">

    <context:component-scan base-package="com.mkyong.common.controller" />

    <mvc:interceptors>
        <mvc:interceptor>
            <bean class="com.mykong.common.interceptor.MyInterceptor" />
            <mvc:mapping path="/**"/>
        </mvc:interceptor>
    </mvc:interceptors>

   <mvc:annotation-driven />

</beans>

Here is web.xml

    <web-app id="WebApp_ID" version="2.4"
    xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee 
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

    <display-name>Spring Web MVC Application</display-name>

    <servlet>
        <servlet-name>mvc-dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>

        <servlet-name>mvc-dispatcher</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/mvc-dispatcher-servlet.xml</param-value>
    </context-param>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

</web-app>

I am running this project on eclipse. I am not able to see "Pre-handle","Post-handle" and "After completion handle" being printed in the Console tab of eclipse.

Any help would be appreciated. Thanks :)

Answer 1

Change your mvc-dispatcher servlet mapping in your web.xml as follows:

 <servlet-mapping>
        <servlet-name>mvc-dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
 </servlet-mapping>

Also, edit your mvc:interceptors in mvc-dispatcher-servlet.xml file as below:

<mvc:interceptors>
            <mvc:interceptor>
                <mvc:mapping path="/**"/>
                <bean class="com.mykong.common.interceptor.MyInterceptor" />           
            </mvc:interceptor>
</mvc:interceptors>

Optionally, you can remove below entry from web.xml , as by default Spring looks for servletName-servlet.xml inside your WEB-INF folder:

 <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/mvc-dispatcher-servlet.xml</param-value>
 </context-param>

 <listener>
      <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
 </listener>