Sonata\Component\Invoice\InvoiceInterface::getId PHP Méthode

    public function getId();

 /**
  * {@inheritdoc}
  */
 public function invoice(InvoiceInterface $invoice)
 {
     if (!$invoice->getId()) {
         throw new \RuntimeException('The invoice is not persisted into the database');
     }
     $this->generateReference($invoice, $this->registry->getManager()->getClassMetadata(get_class($invoice))->table['name']);
 }