package com.listener;

import javax.servlet.ServletContextAttributeEvent;

import javax.servlet.ServletContextAttributeListener;

/**

* 上下文属性监听

*/

public class ServletContextAttributeListenerDemo implements

ServletContextAttributeListener {

public void attributeAdded(ServletContextAttributeEvent event) {

// 属性增加时触发

System.out.println("** 增加属性 --> 属性名称：" + event.getName() + ", 属性内容：" + event.getValue());

}

public void attributeRemoved(ServletContextAttributeEvent event) {

// 属性删除时触发

System.out.println("** 删除属性 --> 属性名称：" + event.getName() + ", 属性内容：" + event.getValue());

}

public void attributeReplaced(ServletContextAttributeEvent event) {

// 属性替换时触发

System.out.println("** 增加属性 --> 属性名称：" + event.getName() + ", 属性内容：" + event.getValue());

}

}

 

web.xml

<listener>

<listener-class>com.listener.ServletContextAttributeListenerDemo</listener-class>

</listener>