@Override
    public synchronized void remove(final ExplorerTreeNode node) {
        if (node != null && isPersistent(node)) {
            removeTree(node.getId());
        } else {
            throw new IllegalArgumentException("Node to remove is null or not persistent: " + node);
        }
    }
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