资源简介
基本功能和QQ类似。首先，系统分为两大部分，第一部分是客户端，是用户使用的部分，第二部分就是服务器，所有的客户端都是通过服务器来进行用户身份验证及聊天转接的。客户端提供主要的界面及服务请求，如：登录界面、注册界面、找回密码界面、主窗体界面、聊天界面、信息查看界面等。客户端主要提供服务请求界面，核心的业务逻辑处理主要由服务器提供，并向客户端发送请求的结果。同时，服务器要能提供服务的开启、关闭功能及查看在线人数及客户端登录日志。
代码片段和文件信息
/*
* Licensed to the Apache Software Foundation （ASF） under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License Version 2.0
* （the “License“）; you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing software
* distributed under the License is distributed on an “AS IS“ BASIS
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package mypackage;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Simple servlet to validate that the Hello World example can
* execute servlets. In the web application deployment descriptor
* this servlet must be mapped to correspond to the link in the
* “index.html“ file.
*
* @author Craig R. McClanahan
*/
public final class Hello extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* Respond to a GET request for the content produced by
* this servlet.
*
* @param request The servlet request we are processing
* @param response The servlet response we are producing
*
* @exception IOException if an input/output error occurs
* @exception ServletException if a servlet error occurs
*/
@Override
public void doGet（HttpServletRequest request
HttpServletResponse response）
throws IOException ServletException {
response.setContentType（“text/html“）;
PrintWriter writer = response.getWriter（）;
writer.println（““）;
writer.println（““）;
writer.println（“tle>Sample Application Servlet Page tle>“）;
writer.println（““）;
writer.println（““）;
writer.println（““）;
writer.println（““）;
writer.println（““）;
writer.println（““）;
writer.println（“ “）;
writer.println（““）;
writer.println（“Sample Application Servlet
“）;
writer.println（“This is the output of a servlet that is part of“）;
writer.println（“the Hello World application.“）;
writer.println（“ “）;
writer.println（“ “）;
writer.println（““）;
writer.println（““）;
writer.println（“