import java.io.*;
import java.net.*;
public class EchoServer implements Runnable{
    Socket conn; /* member variable, for run() */
    public EchoServer(Socket s){ conn = s; }
    public static void main(String argv[]) throws IOException {
	/* run is a member method, must create object to call it */
	ServerSocket server = new ServerSocket(Integer.valueOf(argv[0]).intValue());
	/* provide the socket as argument to the constructor call */
	while(true) new Thread(new EchoServer(server.accept())).start();
    }
    public void run() {
	try{ /* run does not throw any exceptions so we must try and catch */
	    InputStream in = conn.getInputStream();
	    OutputStream out = conn.getOutputStream();
	    byte[] buffer = new byte[8192];
	    int n;
	    while((n = in.read(buffer, 0, 8192))!=-1)
		out.write(buffer, 0, n);
	    in.close();
	    out.close();
	    conn.close();
	}
	/* handle exception */
	catch(IOException e){
	    e.printStackTrace();
	}
    }
}