import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;
public class MainClass {
public static void main(String[] args) {
String host = "localhost";
for (int i = 1; i < 1024; i++) {
try {
Socket s = new Socket(host, i);
System.out.println("There is a server on port " + i + " of " + host);
} catch (UnknownHostException ex) {
System.err.println(ex);
break;
} catch (IOException ex) {
}
}
}
}