public function flush()
{
$allPersisted = [];
$allRemoved = [];
foreach ($this->getLoadedRepositories() as $repository) {
list($persisted, $removed) = $repository->doFlush();
$allPersisted = array_merge($allPersisted, $persisted);
$allRemoved = array_merge($allRemoved, $removed);
}
$this->onFlush($allPersisted, $allRemoved);
}