/* MultiHosts.java  ----------------------------------------------------
   Version 1.0

   Example of how to get a string argument, and spawn a listener at that port.
   C. Elliott 2010-03-12     

   -------------------------------------------------------------------------*/


import java.io.*;  // Get the Input Output libraries
import java.net.*; // Get the Java networking libraries

class NullWorker extends Thread {     // Class definition
    Socket sock;                      // Class member, socket, local to worker
    NullWorker (Socket s) {sock = s;} // Constructor, assign arg s to local sock

    public void run(){
	System.out.println("How did you ever get here? Kill me!\n");
    }
}

public class MultiHosts {

    public static boolean controlSwitch = true;

    public static void main(String a[]) throws IOException {
	int q_len = 6;    /* Number of requests for OpSys to queue */
	int port = 45050; /* Default port value */

	if (a.length == 1) try { // Have an argument, so use it
	    port = Integer.parseInt(a[0]);
	} 
	catch(NumberFormatException Ex) { 
	    /* Have checked that a[0] is actually a number */
	    System.out.println(a[0] + " is not an Integer"); 
	    System.exit(5);
	} 

	Socket sock;
	ServerSocket servsock = new ServerSocket(port, q_len);

	System.out.println("Elliott's NullServer running at " + port + "\n");
	System.out.println("I do nothing, kill me now!\n");
	while (controlSwitch) {
	    // wait for the next client connection:
	    sock = servsock.accept();
	    new NullWorker (sock).start();
	}
    }
}