code: private void fireSocketClosedEvent(final Exception listenerException) {
      synchronized (listenerList) {
          for (Iterator iter = listenerList.iterator(); iter.hasNext();) {
              SocketNodeEventListener snel =
                      (SocketNodeEventListener) iter.next();
              if (snel != null) {
                  snel.socketClosedEvent(listenerException);
              }
          }
      }
    }
docs: Notifies all registered listeners regarding the closing of the Socket.
  @param listenerException listener exception