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

class Main
{
    public static void main(String[] args) throws IOException
    {
        byte[] data  = new byte[20];
        String output = "";

        ServerSocket socket = SocketFactory.buildSocket();

        Socket clientSocket = socket.accept(); //oczekiwanie na polaczenie, oraz akceptacja

        InputStream input = clientSocket.getInputStream();
        
        input.read(data, 0, 20);
        output = new String(data, 0, 20);
        System.out.println(output);


    }
}