网络聊天室简单的实现 用到session request response application等

doLogin操作
<%@page import=“java.util.ArrayList”%>
<%@page import=“java.util.List”%>
<%@ page language=“java” contentType=“text/html; charset=UTF-8”
pageEncoding=“UTF-8”%>
<%
//设置请求响应的编码集
request.setCharacterEncoding(“UTF-8”);
response.setCharacterEncoding(“UTF-8”);
//从页面获取用户名
String username=request.getParameter(“username”);
if(nullusername || “”.equals(username)){
response.sendRedirect(“login.jsp”);
}else{
//获取在线用户名
List users=(List)application.getAttribute(“users”);
if(nullusers){//第一个用户登录
users=new ArrayList();
}
users.add(username);
application.setAttribute(“users”, users);

//当前session中要存储用户名
session.setAttribute("username", username);
response.sendRedirect("talk.jsp");

}
%>

doLogout操作
<%@page import=“java.util.List”%>
<%@ page language=“java” contentType=“text/html; charset=UTF-8”
pageEncoding=“UTF-8”%>
<%
//设置请求响应的编码集
request.setCharacterEncoding(“UTF-8”);
response.setCharacterEncoding(“UTF-8”);
//获取在线用户名
List users=(List)application.getAttribute(“users”);
//获取传入用户名
String uname=request.getParameter(“username”);
users.remove(uname);
//application对象重新存入新的List
application.setAttribute(“users”, users);
//移除session中的属性
session.removeAttribute(“username”);
response.sendRedirect(“login.jsp”);
%>

doTalk操作

<%@page import=“java.util.ArrayList”%>
<%@page import=“java.util.List”%>
<%@page import=“com.sun.glass.ui.Pixels.Format”%>
<%@page import=“java.text.SimpleDateFormat”%>
<%@page import=“java.util.Date”%>
<%@ page language=“java” contentType=“text/html; charset=UTF-8”
pageEncoding=“UTF-8”%>
<%
//设置请求响应的编码集
request.setCharacterEncoding(“UTF-8”);
response.setCharacterEncoding(“UTF-8”);

//从页面获取内容·
String mood = request.getParameter(“mood”);
String msg =request.getParameter(“msg”);
//获取用户名
String username=(String)session.getAttribute(“username”);
Date date = new Date();
SimpleDateFormat format = new SimpleDateFormat(“yyyy-MM-dd HH:mm:ss”);
//String content=username+" “+mood+” “+format.format(date)+”
"+msg;
String content="

"+format.format(date)+"
"+username+" “+mood+“说：”
+”

"+msg+"";

//获取聊天记录
List words=(List)application.getAttribute(“words”);
if(null==words){
words=new ArrayList();
}
words.add(content);
application.setAttribute(“words”, words);
response.sendRedirect(“talk.jsp”);
%>