public function find( $primaryKeys )
    {
        if ( is_array( $primaryKeys ) )
        {
            $primaryKeys = reset( $primaryKeys );
        }

        $rootId = ( (int) $primaryKeys ) ?: null;

        return $this->createStructure( array(
            'rootId'    => $rootId,
            'extra'     => $this->getExtraMapper()
                                ->findByRoot( $rootId ),
            'rules'     => $this->getRuleMapper()
                                ->findAllByRoot(
                                    $rootId,
                                    $this->getRuleOrder()
                                ),
        ) );
    }