cara dapetin connection buat symfony doctrine

public function save(Doctrine_Connection $conn = null)
{
  // ...
 
  $conn = $conn ? $conn : $this->getTable()->getConnection();
  $conn->beginTransaction();
  try
  {
    $ret = parent::save($conn);
 
    $this->updateLuceneIndex();
 
    $conn->commit();
 
    return $ret;
  }
  catch (Exception $e)
  {
    $conn->rollBack();
    throw $e;
  }
}