public final static long getParentId(final DocumentImpl doc, final long gid) { final int level = doc.getTreeLevel(gid); return getParentId(doc, gid, level);
public final static long getParentId(NodeProxy node) { return getParentId(node.getDocument(), node.getGID());
    public final static long getParentId(final DocumentImpl doc, final long gid) {        final int level = doc.getTreeLevel(gid);        return getParentId(doc, gid, level);    }