code: public void sendToAllExcept(String topicURI, Object event,
  			Set<String> excludeWebSocketSessionIds) {
  		EventMessage eventMessage = new EventMessage(topicURI, event);
  		eventMessage.setExcludeWebSocketSessionIds(excludeWebSocketSessionIds);
  		send(eventMessage);
  	}
docs: Send an {@link EventMessage} to every client that is currently subscribed to the
  provided topicURI except the ones listed in the excludeSessionIds set.
  
  @param topicURI the name of the topic
  @param event the payload of the {@link EventMessage}
  @param excludeWebSocketSessionIds a set of WebSocket session ids that will be
  excluded. If null or empty no client will be excluded.