private function addInheritedNamedQueries(ClassMetadata $subClass, ClassMetadata $parentClass)
    {
        foreach ($parentClass->namedQueries as $name => $query) {
            if ( ! isset ($subClass->namedQueries[$name])) {
                $subClass->addNamedQuery(array(
                    'name'  => $query['name'],
                    'query' => $query['query']
                ));
            }
        }
    }