多用户在线聊天服务端

[java]代码库

import java.net.*;
import java.util.*;
import java.io.*;

public class ChatServer{
	public static void main(String[] args){
		Hashtable<String,DataOutputStream> userList = new
			Hashtable<String,DataOutputStream>();
		String name;
		DataInputStream dis;
		DataOutputStream dos;
		
		try{
			ServerSocket ss = new ServerSocket(8999);
			while(true){
				Socket s = ss.accept();
				dis = new DataInputStream(s.getInputStream());
				dos = new DataOutputStream(s.getOutputStream());
				name = dis.readUTF();
				userList.put(name,dos);
				new MyServerReader(name,dis,userList).start();
			}
		}catch(Exception e){
			e.printStackTrace();
		}
	}
}

class MyServerReader extends Thread{
	private String name;
	private DataInputStream dis;
	private Hashtable<String,DataOutputStream> userList;
	
	public MyServerReader(String name,DataInputStream dis,Hashtable<String,DataOutputStream> userList){
		this.name = name;
		this.dis = dis;
		this.userList = userList;
	}
	
	public void run(){
		String info;
		try{
			transimitMessage(name+"in!","--Server Info--");
			while(true){
				info  = dis.readUTF();
				if(info.equals("bye")){
					DataOutputStream dos = (DataOutputStream)(userList.get(name));
					Thread.sleep(1000);
					dos.close();
					dis.close();
					userList.remove(name);
					transimitMessage(name+"out","--Server Info--");
					break;
				}else if(info.length()>0){
					transimitMessage(info,name);
				}
			}
		}catch(Exception e){
			e.printStackTrace();
		}
	}
	
	public void transimitMessage(String msg,String name){
		Collection doses = userList.values();
		DataOutputStream dos;
		for(Object o:doses){
			dos = (DataOutputStream)o;
			try{
				dos.writeUTF(name+":"+msg);
			}catch(Exception e){
				e.printStackTrace();
			}
		}
	}
}