1实现HttpSessionListener和ServletContextListener，2个接口

2然后在contextInitialized初始化方法里面：

        ServletContext application = event.getServletContext();  
        WebApplicationContext appctx = WebApplicationContextUtils.getWebApplicationContext(application);  
        newsSubmissionService = appctx.getBean(NewsSubmissionService.class);

3在web.xml里面配置

<listener>  
        <listener-class>com.guduo.log.TaskReBack</listener-class>  
</listener>

监听器以及在监听类里面获得bean的方法