/** * {@inheritdoc} * * @throws InvalidEventException * * @since Method available since Release 2.2.0 */ public function addTransitionEvent(TransitionEventInterface $event) { if ($event->getEventId() != EventInterface::EVENT_START) { throw new InvalidEventException(sprintf('The transition event for the state "%s" should be "%s", "%s" is specified.', $this->getStateId(), EventInterface::EVENT_START, $event->getEventId())); } parent::addTransitionEvent($event); }