/** Stop talking to the server */
 public void stop() {
   if (socket != null) {
     // Close all the streams and socket
     if (out != null) {
       try {
         out.close();
       } catch (IOException ioe) {
       }
       out = null;
     }
     if (in != null) {
       try {
         in.close();
       } catch (IOException ioe) {
       }
       in = null;
     }
     if (socket != null) {
       try {
         socket.close();
       } catch (IOException ioe) {
       }
       socket = null;
     }
   } else {
     // Already stopped
   }
   // Make sure the right buttons are enabled
   start_button.setEnabled(true);
   stop_button.setEnabled(false);
   setStatus(STATUS_STOPPED);
 }