public function next(ContextInterface $context)
{
if (null === $this->current) {
throw new Exception\NotInitializedWorkflowException();
}
$transitions = $this->current->getOpenTransitions($context);
if (0 === count($transitions)) {
throw new Exception\NoOpenTransitionException();
} elseif (1 < count($transitions)) {
throw new Exception\MoreThanOneOpenTransitionException();
}
$transition = array_pop($transitions);
$token = $transition->getDestination()->getName();
$this->initialize($token);
$this->eventDispatcher->dispatch($token, new Event($context, $token));
return $this;
}