/**
* Get a hierarchy driver appropriate to the current object. (May be false if
* disabled/unavailable).
*
* @return \VuFind\Hierarchy\Driver\AbstractBase|bool
*/
public function getHierarchyDriver()
{
if (null === $this->hierarchyDriver && null !== $this->hierarchyDriverManager) {
$type = $this->getHierarchyType();
$this->hierarchyDriver = $type ? $this->hierarchyDriverManager->get($type) : false;
}
return $this->hierarchyDriver;
}
