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

        return (node == null)
               ? null
               : node.getLeft(index);
    }
private static <K,V> Node<K,V> getLeftChild(final Node<K,V> node, final int index) {

        return (node == null)
               ? null
               : node.getLeft(index);
    }
private static < K , V > Node < K , V > getLeftChild ( final Node < K , V > node , final int index ) { return ( node == null ) ? null : node . getLeft ( index ) ; }
get a node's left child. mind you, the node may not exist. no
problem

@param node the node (may be null) in question
@param index KEY or VALUE
get a node s left child . mind you the node may not exist . no problem