src/main/java/com/workplacesystems/utilsj/collections/TransactionalBidiTreeMap.java
private Node<K,V> nextGreater(final Node<K,V> node, final int index) {

        Node<K,V> rval;

        if (node == null) {
            rval = null;
        } else if (node.getRight(index) != null) {

            // everything to the node's right is larger. The least of
            // the right node's descendants is the next larger node
            rval = leastNode(node.getRight(index), index);
        } else {

            // traverse up our ancestry until we find an ancestor that
            // is null or one whose left child is our ancestor. If we
            // find a null, then this node IS the largest node in the
            // tree, and there is no greater node. Otherwise, we are
            // the largest node in the subtree on that ancestor's left
            // ... and that ancestor is the next greatest node
            Node<K,V> parent = node.getParent(index);
            Node<K,V> child  = node;

            while ((parent != null) && (child == parent.getRight(index))) {
                child  = parent;
                parent = parent.getParent(index);
            }

            rval = parent;
        }

        return rval;
    }
private Node<K,V> nextGreater(final Node<K,V> node, final int index) {

        Node<K,V> rval;

        if (node == null) {
            rval = null;
        } else if (node.getRight(index) != null) {

            // everything to the node's right is larger. The least of
            // the right node's descendants is the next larger node
            rval = leastNode(node.getRight(index), index);
        } else {

            // traverse up our ancestry until we find an ancestor that
            // is null or one whose left child is our ancestor. If we
            // find a null, then this node IS the largest node in the
            // tree, and there is no greater node. Otherwise, we are
            // the largest node in the subtree on that ancestor's left
            // ... and that ancestor is the next greatest node
            Node<K,V> parent = node.getParent(index);
            Node<K,V> child  = node;

            while ((parent != null) && (child == parent.getRight(index))) {
                child  = parent;
                parent = parent.getParent(index);
            }

            rval = parent;
        }

        return rval;
    }
get the next larger node from the specified node

@param node the node to be searched from
@param index KEY or VALUE

@return the specified node