Web项目实现ServletContextListener接口

本文主要是介绍Web项目实现ServletContextListener接口，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

源码

package javax.servlet;import java.util.EventListener;/***  Implementations of this interface receive notifications *  about changes to the servlet context of the  web*  application they are part of. To receive notification events,*  the implementation class must be configured in the*  deployment descriptor for the web application.* @see ServletContextEvent* @since v 2.3*/public interface ServletContextListener extends EventListener {/**** Notification that the web application initialization process *  is starting. All ServletContextListeners are notified of *  context initialization before any filter or servlet in the *  web application is initialized.* @param sce Information about the ServletContext that was * initialized* 当Servlet 容器启动Web 应用时调用该方法。*/public void contextInitialized(ServletContextEvent sce);/**** Notification that the servlet context is about to be shut *  down. All servlets and filters have been destroy()ed *  before any ServletContextListeners are notified of context *  destruction.* @param sce Information about the ServletContext that was * destroyed* 当Servlet 容器终止Web 应用时调用该方法。*/public void contextDestroyed(ServletContextEvent sce);
}

介绍

ServletContextListener本质上就是一个监听器，监听 Web 应用的生命周期

  在 Servlet API 中有一个 ServletContextListener 接口，它能够监听 ServletContext 对象的生命周期，实际上就是监听 Web 应用的生命周期。

  当Servlet 容器启动或终止Web 应用时，会触发ServletContextEvent 事件，该事件由ServletContextListener 来处理。在 ServletContextListener 接口中定义了处理ServletContextEvent 事件的两个方法。

项目代码实现

定义一个监听器

public class OperationReplyListener implements ServletContextListener {private static final Log logger = LogFactory.getLog(OperationReplyListener.class);final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1);  public void contextDestroyed(ServletContextEvent sce) {}public void contextInitialized(ServletContextEvent sce) {logger.info("定时器启动...");OperationReplyTask operationReplyTask = new OperationReplyTask();scheduler.scheduleAtFixedRate(operationReplyTask, 2, 5, TimeUnit.SECONDS);}
}

web.xml中配置监听器

<listener><listener-class>com.sto.rookie.timer.OperationReplyListener</listener-class>
</listener>

这篇关于Web项目实现ServletContextListener接口的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！

---