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

public class Server extends Thread {
    ClientHandlerFactory chf;
    ServerSocket ss;

    public Server(int port, ClientHandlerFactory chf) {
        this.chf = chf;
        try {
            ss = new ServerSocket(port);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void run() {
        while (true) {
            try {
                Socket s = ss.accept();
                ServerBehavior sb = chf.getNewClientHandler();
                sb.setStreams(s.getOutputStream(), s.getInputStream());
                sb.setSocket(s);
                (new Thread(sb)).start();
            }
            catch (Exception e) {
                e.printStackTrace();
            }
        }
    }



    // creates the objects that communicate with clients
    public interface ClientHandlerFactory {
        public ServerBehavior getNewClientHandler();
    }

    
    // for defining how the server talks to clients
    public static interface ServerBehavior extends Runnable {
        public void setStreams(OutputStream os, InputStream is);
        public void setSocket(Socket s);
        public void closeSocket();
    }

    // just for convenience...
    public static class ServerBehaviorAdapter implements ServerBehavior {
        protected OutputStream os;
        protected InputStream is;
        protected Socket socket;

        public void setStreams(OutputStream os, InputStream is) {
            this.os = os;
            this.is = is;
        }

        public void setSocket(Socket s) {
            socket = s;
        }

        public void closeSocket() {
            try {
                socket.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

        public void run() {
        }
    }
}