private void assertInsertParameters(final ExplorerTreeNode parent,
                                        final ExplorerTreeNode sibling,
                                        final int position) {
        assert parent == null || sibling == null;

        assert sibling == null || position == -1;

    }
Get the root node containing a particular node, or the node itself if it is a root node.
stroom-explorer/stroom-explorer-impl-db/src/main/java/stroom/explorer/impl/db/ExplorerTreeDaoImpl.java