Map<String, HttpSession> map=(Map<String, HttpSession>)

Map<String, HttpSession> map=(Map<String, HttpSession>) sc.getAttribute("users");//保存所有登录有关的map对象

package com.tfy.heima.listener;

import java.util.Collection;

import java.util.Collections;

import java.util.HashMap;

import java.util.Map;

import javax.servlet.ServletContext;

import javax.servlet.http.HttpSession;

import javax.servlet.http.HttpSessionAttributeListener;

import javax.servlet.http.HttpSessionBindingEvent;

import com.tfy.heima.domain.User;

public class OnlineUserListener implements HttpSessionAttributeListener {

//Map<String,HttpSession>

public void attributeAdded(HttpSessionBindingEvent se) {

      HttpSession session=se.getSession();

      Object obj=session.getAttribute("user");

      if(obj!=null && obj instanceof User){

     User user=(User)obj;

     ServletContext sc=session.getServletContext();

     Map<String, HttpSession> map=(Map<String, HttpSession>) sc.getAttribute("users");//保存所有登录有关的map对象

     if(map==null){

     map=Collections.synchronizedMap(new HashMap<String, HttpSession>());

     sc.setAttribute("users", map);

     }

     map.put(user.getUsername(), session);

      }

}

public void attributeRemoved(HttpSessionBindingEvent se) {

}

public void attributeReplaced(HttpSessionBindingEvent se) {

}

}

条回答

本问题标题：Map＜String,HttpSession＞map=(Map＜String,H
本问题地址：http://www.educity.cn/wenda/387230.html