core-bundle/src/Resources/contao/library/Contao/Model/Registry.php
public function register(Model $objModel)
	{
		$intObjectId = spl_object_hash($objModel);

		// The model has been registered already
		if (isset($this->arrIdentities[$intObjectId]))
		{
			return;
		}

		$strTable = $objModel->getTable();

		if (!\is_array($this->arrAliases[$strTable]))
		{
			$this->arrAliases[$strTable] = array();
		}

		if (!\is_array($this->arrRegistry[$strTable]))
		{
			$this->arrRegistry[$strTable] = array();
		}

		$strPk = $objModel->getPk();
		$varPk = $objModel->$strPk;

		if ($varPk === null)
		{
			throw new \RuntimeException('The primary key has not been set');
		}

		// Another model object is pointing to the DB record already
		if (isset($this->arrRegistry[$strTable][$varPk]))
		{
			throw new \RuntimeException("The registry already contains an instance for $strTable::$strPk($varPk)");
		}

		$this->arrIdentities[$intObjectId] = $objModel;
		$this->arrRegistry[$strTable][$varPk] = $objModel;

		// Allow the model to modify the registry
		$objModel->onRegister($this);
	}
public function register(Model $objModel)
	{
		$intObjectId = spl_object_hash($objModel);

		// The model has been registered already
		if (isset($this->arrIdentities[$intObjectId]))
		{
			return;
		}

		$strTable = $objModel->getTable();

		if (!\is_array($this->arrAliases[$strTable]))
		{
			$this->arrAliases[$strTable] = array();
		}

		if (!\is_array($this->arrRegistry[$strTable]))
		{
			$this->arrRegistry[$strTable] = array();
		}

		$strPk = $objModel->getPk();
		$varPk = $objModel->$strPk;

		if ($varPk === null)
		{
			throw new \RuntimeException('The primary key has not been set');
		}

		// Another model object is pointing to the DB record already
		if (isset($this->arrRegistry[$strTable][$varPk]))
		{
			throw new \RuntimeException("The registry already contains an instance for $strTable::$strPk($varPk)");
		}

		$this->arrIdentities[$intObjectId] = $objModel;
		$this->arrRegistry[$strTable][$varPk] = $objModel;

		// Allow the model to modify the registry
		$objModel->onRegister($this);
	}
Register a model in the registry

@param Model $objModel The model object

@throws \RuntimeException If the instance exists already