public function getNodeByIdentifier($identifier)
    {
        $node = $this->firstLevelNodeCache->getByIdentifier($identifier);
        if ($node !== false) {
            return $node;
        }
        $nodeData = $this->nodeDataRepository->findOneByIdentifier($identifier, $this->getWorkspace(), $this->dimensions, $this->removedContentShown);
        if ($nodeData !== null) {
            $node = $this->nodeFactory->createFromNodeData($nodeData, $this);
        } else {
            $node = null;
        }
        $this->firstLevelNodeCache->setByIdentifier($identifier, $node);
        return $node;
    }