Jsp 監聽請求的兩個監聽器學習筆記

我們下面這個類，通過實現兩個介面，從而我們這個類可以有多個作用(監聽請求和請求範圍內的屬性的變化)

1.編寫我們的類

代碼如下

複製代碼

package org.Rudiment.Listener; import javax.servlet.ServletRequestAttributeEvent; import javax.servlet.ServletRequestAttributeListener; import javax.servlet.ServletRequestEvent; import javax.servlet.ServletRequestListener; import javax.servlet.http.HttpServletRequest; public class MyRequestListener implements ServletRequestListener, ServletRequestAttributeListener {     @Override     public void attributeAdded(ServletRequestAttributeEvent arg0) {         System.out.println("Request範圍中的屬性:" + arg0.getName() + " 被添加,數值為:" + arg0.getValue());     }     @Override     public void attributeRemoved(ServletRequestAttributeEvent arg0) {         System.out.println("Request範圍中的屬性:" + arg0.getName() + " 被刪除,數值為:" + arg0.getValue());     }     @Override     public void attributeReplaced(ServletRequestAttributeEvent arg0) {         System.out.println("Request範圍中的屬性:" + arg0.getName() + " 數值更新為:" + arg0.getValue());     }     @Override     public void requestDestroyed(ServletRequestEvent arg0) {         HttpServletRequest request = (HttpServletRequest)arg0.getServletRequest();         System.out.println("請求即將結束"  );     }     @Override     public void requestInitialized(ServletRequestEvent arg0) {         HttpServletRequest request = (HttpServletRequest)arg0.getServletRequest();         System.out.println("請求即將開始,請求來自" + request.getHeader("Referer") + "發向" + request.getRequestURI());     } }

2.在web.xml 中配置我們的監聽器

代碼如下	複製代碼
<listener>     <listener-class>org.Rudiment.Listener.MyRequestListener</listener-class> </listener>