在聊天室中用监听器.rar

package com.xfaccp; import java.util.ArrayList; import javax.servlet.ServletContext; import javax.servlet.ServletContextEvent; import javax.servlet.ServletContextListener; import javax.servlet.http.*; public class SessionLinstenerTest implements HttpSessionListener ,HttpSessionAttributeListener,ServletContextListener{ ServletContext context=null; public void sessionCreated(HttpSessionEvent arg0) { // TODO Auto-generated method stub } public void sessionDestroyed(HttpSessionEvent event) { // TODO Auto-generated method stub System.out.println("session失效"); ArrayList list=(ArrayList)context.getAttribute("users"); String temp=event.getSession().getAttribute("nickName").toString(); for(int i=0;i<list.size();i++) { if(list.get(i).toString().equals(temp)) { list.remove(i); } } } public void attributeAdded(HttpSessionBindingEvent event) { // TODO Auto-generated method stub System.out.println("session添加属性"); ArrayList list=(ArrayList)context.getAttribute("users"); list.add(event.getValue()); context.setAttribute("users", list); } public void attributeRemoved(HttpSessionBindingEvent arg0) { // TODO Auto-generated method stub } public void attributeReplaced(HttpSessionBindingEvent arg0) { // TODO Auto-generated method stub } public void contextDestroyed(ServletContextEvent arg0) { // TODO Auto-generated method stub } public void contextInitialized(ServletContextEvent application) { // TODO Auto-generated method stub System.out.println("上下文初始化"); ArrayList list=new ArrayList(); context=application.getServletContext(); context.setAttribute("users", list); } }