监听器 ServletContextListener 监听servlet的初始化和结束 httpSessionListener 监听session的创建和结束 ,可以利用这个来统计在线登录的人数.. package com.zh; import javax.servlet.http.HttpSessionEvent; import javax.servlet.http.HttpSessionListener; public class LoginListener implements HttpSessionListener{ private static int count; public static int getCount(){ return count; } public void sessionCreated(HttpSessionEvent arg0) { // TODO Auto-generated method stub count++; } public void sessionDestroyed(HttpSessionEvent arg0) { // TODO Auto-generated method stub count--; } } 注意要在web.xml文件中 设置 <listener> <listener-class>com.zh.Test1</listener-class> </listener> ServletContextAttributeListener 当servletContext对象被设置,删除,替换 HttpSessionAttributeListener 当HttpSession对象被设置,删除,替换 ServletRequestAttributeListener 当ServletRequest对象被设置,删除,替换 HttpSessionBindingListener 当HttpSession中添加属性和删除属性 注意: HttpSessionBindingListener不用在web.xml中设置
监听器
ServletContextListener 监听servlet的初始化和结束
httpSessionListener 监听session的创建和结束 ,可以利用这个来统计在线登录的人数..
package com.zh;
import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;
public class LoginListener implements HttpSessionListener{
private static int count;
public static int getCount(){
return count;
}
public void sessionCreated(HttpSessionEvent arg0) {
// TODO Auto-generated method stub
count++;
}
public void sessionDestroyed(HttpSessionEvent arg0) {
// TODO Auto-generated method stub
count--;
}
}
注意要在web.xml文件中 设置
<listener>
<listener-class>com.zh.Test1</listener-class>
</listener>
ServletContextAttributeListener 当servletContext对象被设置,删除,替换
HttpSessionAttributeListener 当HttpSession对象被设置,删除,替换
ServletRequestAttributeListener 当ServletRequest对象被设置,删除,替换
HttpSessionBindingListener 当HttpSession中添加属性和删除属性
注意: HttpSessionBindingListener不用在web.xml中设置