JAVA聊天室（二代）代码仅为原来的一半！性能进一步提升，性能允许的基础上可连接无数客户端，改进了下线CPU占有暴增情况，实现指定人员聊天功能。。：管天阳的日志登录桌面登录后用户列表可以显示可指定人员单独聊天上线客户端提醒退出时列表可显示，每个客户端的用户项也将消失。。下面是代码:1.服务器：packagecom.zzk;importjava.awt.BorderLayout;importjava.awt.Frame;importjava.awt.Image;importjava.awt.MenuItem;importjava.awt.PopupMenu;importjava.awt.SystemTray;importjava.awt.TrayIcon;importjava.awt.event.ActionEvent;importjava.awt.event.ActionListener;importjava.awt.event.MouseAdapter;importjava.awt.event.MouseEvent;importjava.awt.event.WindowAdapter;importjava.awt.event.WindowEvent;importjava.io.IOException;importjava.io.ObjectInputStream;importjava.io.PrintWriter;importjava.ServerSocket;importjava.Socket;importjava.URL;importjava.util.Hashtable;importjava.util.Iterator;importjava.util.Set;importjava.util.Vector;importjavax.swing.ImageIcon;importjavax.swing.JFrame;importjavax.swing.JScrollPane;importjavax.swing.JTextArea;publicclassChatServerFrameextendsJFrame{privateJTextAreata_info;privateServerSocketserver;//声明ServerSocket对象privateSocketsocket;//声明Socket对象socketprivateHashtable<String,Socket>map=newHashtable<String,Socket>();//用于存储连接到服务器的用户和客户端套接字对象publicvoidcreateSocket(){try{server=newServerSocket(1982);//创建服务器套接字对象while(true){ta_info.append("等待新客户连接......\n");socket=server.accept();//获得套接字对象ta_info.append("客户端连接成功。"+socket+"\n");newServerThread(socket).start();//创建并启动线程对象}}catch(IOExceptione){e.printStackTrace();}}classServerThreadextendsThread{Socketsocket;publicServerThread(Socketsocket){this.socket=socket;}publicvoidrun(){try{ObjectInputStreamins=newObjectInputStream(socket.getInputStream());while(true){Vectorv=null;try{v=(Vector)ins.readObject();}catch(ClassNotFoundExceptione){e.printStackTrace();}if(v!=nullv.size()>0){for(inti=0;i<v.size();i++){Stringinfo=(String)v.get(i);//读取信息Stringkey="";if(info.startsWith("用户：")){//添加登录用户到客户端列表key=info.substring(3,info.length());//获得用户名并作为键使用map.put(key,socket);//添加键值对Set<String>set=map.keySet();//获得集合中所有键的Set视图Iterator<String>keyIt=set.iterator();//获得所有键的迭代器while(keyIt.hasNext()){StringreceiveKey=keyIt.next();//获得表示接收信息的键Sockets=map.get(receiveKey);//获得与该键对应的套接字对象PrintWriterout=newPrintWriter(s.getOutputStream(),true);//创建输出流对象Iterator<String>keyIt1=set.iterator();//获得所有键的迭代器while(keyIt1.hasNext()){StringreceiveKey1=keyIt1.next();//获得键，用于向客户端添加用户列表out.println(receiveKey1);//发送信息out.flush();//刷新输出缓冲区}}}elseif(info.startsWith("退出：")){key=info.substring(3);//获得退出用户的键map.remove(key);//删除键值对Set<String>set=map.keySet();//获得集合中所有键的Set视图Iterator<String>keyIt=set.iterator();//获得所有键的迭代器while(keyIt.hasNext()){StringreceiveKey=keyIt.next();//获得表示接收信息的键Sockets=map.get(receiveKey);//获得与该键对应的套接字对象PrintWriterout=newPrintWriter(s.getOutputStream(),true);//创建输出流对象out.println("退出："+key);//发送信息out.flush();//刷新输出缓冲区}}else{//转发接收的消息key=info.substring(info.indexOf("：发送给：")+5,info.indexOf("：的信息是："));//获得接收方的key值,即接收方的用户名（因为substring起始索引包括，结尾索引不包括所...