import org.infinispan.tree.Fqn;
import org.infinispan.tree.Node;
import org.infinispan.tree.TreeCache;

public class TreeCacheUtil {

    /**
     * Gets the value for the given FQN and key.
     * <p>
     * Traverses the parents of the given FQN to reset their idle times.
     *
     * @param fqn the FQN
     * @param key the key
     * @return value of the FQN and key; or null if non-existent
     */
    private static Object getAndTouchParents(TreeCache cache, String fqn, String key) {
        Object value = null;
        Node<Object, Object> node = cache.getNode(fqn);
        if (node != null) {
            value = node.get(key);
            Fqn parentFqn;
            do {
                Node<Object, Object> parent = node.getParent();
                parentFqn = parent.getFqn();
                if (parentFqn != null) {
                    cache.getNode(parentFqn); // touch the parent to reset the idle time
                }
            } while (parentFqn != null && !parentFqn.isRoot());
        }
        return value;
    }
}