code: @Override
      public void unsubscribeAll(EventPublisher source) {
  	checkPermission();
  	if (source == null) {
  	    throw new IllegalArgumentException("Parameter cannot be null");
  	}
  	super.unsubscribeAll(source);
      }
docs: /* (non-Javadoc)
  @see com.github.thehilikus.events.event_manager.SubscriptionManager#cleanPublisher(com.github.thehilikus.events.event_manager.api.EventPublisher)