class FastLevelIndexWalker implements LevelIndexWalker<T> {

    @Override
    public List<T> find() {
        LevelNode<T> node = find(index.getRoot(), 0);
        return node != null ? node.getLeafList() : null;
    }

    public  FastLevelIndexWalker(LevelIndex<T> index, String... levelValues);

}