protected function initializeConnection()
{
if (!$this->entityManager instanceof EntityManager) {
$this->outputLine('This command only supports database connections provided by the Doctrine ORM Entity Manager.
However, the current entity manager is an instance of %s.', array(get_class($this->entityManager)));
$this->quit(1);
}
$this->dbalConnection = $this->entityManager->getConnection();
}