/**
* Returns the persistent object of class $class with id $id or null.
*
* This method is equivalent to {@link load()} except that it returns null
* instead of throwing an exception, if the desired object does not exist.
* A null value will not be recorded in the identity map, so a second
* attempt to load the object of $class with $id will result in another
* database query.
*
* @param string $class
* @param int $id
*
* @return ezcPersistentObject|null
*/
public function loadIfExists($class, $id)
{
$idMap = $this->properties['identityMap'];
if (!$this->properties['options']->refetch) {
$identity = $idMap->getIdentity($class, $id);
if ($identity !== null) {
return $identity;
}
}
$identity = $this->session->loadIfExists($class, $id);
if ($identity !== null) {
$idMap->setIdentity($identity);
}
return $identity;
}
