code: protected function getMetaModel($metaModelId)
      {
          if (null === $this->factory) {
              throw new \RuntimeException('No factory set.');
          }
  
          $metaModelName = $this->factory->translateIdToMetaModelName($metaModelId);
          $metaModel     = $this->factory->getMetaModel($metaModelName);
  
          return $metaModel;
      }
docs: Retrieve the MetaModel instance.
  
  @param string $metaModelId The MetaModel id.
  
  @return IMetaModel
  
  @throws \RuntimeException Throws if no factory set.