/**
* {@inheritdoc}
*/
public function execute(Execution $execution)
{
$nodes = $this->process->findInitialNodes();
if (count($nodes) !== 1) {
throw new \RuntimeException(sprintf('No single start node found in process "%s"', $this->process->getTitle()));
}
$startNode = array_shift($nodes);
$sub = $execution->createNestedExecution($this->process, $startNode, true, $this->isolateScope);
foreach ($this->inputs as $target => $source) {
if ($execution->hasVariable($source)) {
$sub->setVariable($target, $execution->getVariable($source));
}
}
$execution->waitForSignal();
$sub->execute($startNode);
}