protected long findValue(DBBroker broker, NodeProxy node)
throws IOException, BTreeException {
if (!lock.hasLock())
{LOG.warn("The file doesn't own a lock");}
final DocumentImpl doc = node.getDocument();
final NodeRef nodeRef = new NativeBroker.NodeRef(doc.getDocId(), node.getNodeId());
// first try to find the node in the index
final long pointer = findValue(nodeRef);
if (pointer == KEY_NOT_FOUND) {
// node not found in index: try to find the nearest available
// ancestor and traverse it