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

public class ChatServer {
	
	boolean started = false;
	ServerSocket ss = null;
	
	List<Client> clients = new ArrayList<Client>();
		
	public static void main(String[] args) {		
		new ChatServer().start();	
	}
	
	public void start(){
		try {
			ss = new ServerSocket(8888);
			started=true;
		}catch (BindException e){
			System.out.println("端口被占用中……");
			System.out.println("請關掉相關程序并重新運行程序 !");
			System.exit(0);
		}
		catch(IOException e){
			e.printStackTrace();
		}
		try{
			while(started){
				Socket s = ss.accept();
				Client c=new Client(s);				
System.out.println("a client accept!");
				clients.add(c);
				new Thread(c).start();
			}		
		}catch (IOException e) {
			try {
				ss.close();
			} catch (IOException e1) {
				e1.printStackTrace();
			}
			e.printStackTrace();
		}
	}

	class Client implements Runnable{
		private Socket s;
		private DataInputStream dis = null;
		private DataOutputStream dos = null;
		private boolean bConnected = false;
		
		public Client(Socket s){
			this.s = s;
			try{
				dis = new DataInputStream(s.getInputStream());
				dos = new DataOutputStream(s.getOutputStream());
				bConnected = true;
			} catch(IOException e){
				e.printStackTrace();
			}
		}
		
		public void run() {
			try{
				while(bConnected){
					String str = dis.readUTF();
					System.out.println(str);
					for(int i = 0; i < clients.size(); i++) {
						Client c = clients.get(i);
						c.send(str);
					}
				}
			} catch (IOException e) {
				try {
					s.close();
					dis.close();
				} catch (IOException e1) {
					e1.printStackTrace();
				}
				//e.printStackTrace();
				System.out.println("client closed !");
			}
		}
		
		public void send(String str) {
			try {
				dos.writeUTF(str);
			} catch(IOException e) {
				e.printStackTrace();
			}
		}
		
	}
}