Method getLeftChild

src/java/org/apache/poi/util/BinaryTree.java:688–692

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

(Node node, int index)

     * @param index _KEY or _VALUE
     */
    private static Node getLeftChild(Node node, int index)
    {
        return (node == null) ? null
                              : node.getLeft(index);
    }

    /**
     * is this node its parent's left child? mind you, the node, or