簡介：監聽器介紹和Servlet3.0的註解自定義原生Listener監聽器實戰

　　自定義Listener(常用的監聽器 servletContextListener、httpSessionListener、servletRequestListener)

　　程式碼示例：

　　RequestListener.java

 1 package net.xdclass.demo.listener;
 2 
 3 import javax.servlet.ServletContextEvent;
 4 import javax.servlet.ServletContextListener;
 
 5 import javax.servlet.annotation.WebListener;
 6 
 7 @WebListener
 8 public class CustomContextListener implements ServletContextListener{
 9 
10     //主要作為資源載入
11     @Override
12     public void contextInitialized(ServletContextEvent sce) {
13         System.out.println("======contextInitialized========");
 
14         
15     }
16 
17     @Override
18     public void contextDestroyed(ServletContextEvent sce) {
19         System.out.println("======contextDestroyed========");
20         
21     }
22 
23 }

　　CustomContextListener.java：

 1 package net.xdclass.demo.listener;
 2 
 3 import javax.servlet.ServletRequestEvent;
 
 4 import javax.servlet.ServletRequestListener;
 5 import javax.servlet.annotation.WebListener;
 6 
 7 @WebListener
 8 public class RequestListener implements ServletRequestListener {
 9 
10     //主要作為統計
11     @Override
12     public void requestDestroyed(ServletRequestEvent sre) {
13         // TODO Auto-generated method stub
14         System.out.println("======requestDestroyed========");
15     }
16 
17     @Override
18     public void requestInitialized(ServletRequestEvent sre) {
19         System.out.println("======requestInitialized========");
20         
21     }
22 
23    
24 }