code: public ScoreNode nextScoreNode() throws IOException
     {
        if (++hitIndex >= size)
        {
           // no more score nodes
           return null;
        }
        else if (hitIndex >= scoreDocs.size())
        {
           // refill at least numHits or twice hitIndex
           this.numHits = Math.max(this.numHits, hitIndex * 2);
           getHits();
        }
        ScoreDoc doc = scoreDocs.get(hitIndex);
        String uuid = reader.document(doc.doc, FieldSelectors.UUID).get(FieldNames.UUID);
        return new ScoreNode(uuid, doc.score, doc.doc);
     }
docs: {@inheritDoc}