/**
  * @param integer $nodeUid
  * @return array|null
  */
 protected function buildPathFromNodeToRoot($nodeUid)
 {
     if (!array_key_exists($nodeUid, $this->nodePathCache)) {
         $node = $this->tree->getNodeByUid($nodeUid);
         $pathFromNodeToRoot = array();
         if ($node instanceof Tx_PtExtbase_Tree_Node) {
             $pathFromNodeToRoot[] = $node;
             while ($node != $this->tree->getRoot()) {
                 $node = $node->getParent();
                 $pathFromNodeToRoot[] = $node;
             }
             $this->nodePathCache[$nodeUid] = $pathFromNodeToRoot;
         } else {
             $this->nodePathCache[$nodeUid] = null;
         }
     }
     return $this->nodePathCache[$nodeUid];
 }