Service/CategoryService.php
private function buildRootNode($node, $tree, $level)
    {
        $node->setLevel($level);
        $tree[$node->getId()] = $node;
    }
private function buildRootNode($node, $tree, $level)
    {
        $node->setLevel($level);
        $tree[$node->getId()] = $node;
    }
private function buildRootNode ( $ node , $ tree , $ level ) { $ node -> setLevel ( $ level ) ; $ tree [ $ node -> getId ( ) ] = $ node ; }
Builds a root node.

@param AbstractCategoryDocument $node
@param \ArrayIterator           $tree
@param int                      $level
Builds a root node .