@Override
public void withTopDocs(IndexSearcher searcher, Query q, TopDocs hits) throws Exception {
  IndexReader reader = searcher.getIndexReader();
  highlighter.setFragmentScorer(new QueryScorer(q));
  // highlighter.setTextFragmenter();  unfortunately no sentence mechanism, not even regex. Default here is trivial
  for (ScoreDoc scoreDoc : docIdOrder(hits.scoreDocs)) {
    Document document = reader.document(scoreDoc.doc, hlFields);
    Fields tvFields = termVecs ? reader.getTermVectors(scoreDoc.doc) : null;
    for (IndexableField indexableField : document) {
      TokenStream tokenStream;
      if (termVecs) {
        tokenStream = TokenSources.getTokenStream(indexableField.name(), tvFields,
            indexableField.stringValue(), analyzer, maxDocCharsToAnalyze);
      } else {
        tokenStream = analyzer.tokenStream(indexableField.name(), indexableField.stringValue());
      }
      // will close TokenStream:
      String[] fragments = highlighter.getBestFragments(tokenStream, indexableField.stringValue(), maxFrags);
      preventOptimizeAway = fragments.length;
    }
  }
}
 

/**
 * NOTE: This method will not preserve the correct field types.
 * 
 * @param preTag
 * @param postTag
 */
public static Document highlight(int docId, Document document, Query query, FieldManager fieldManager,
    IndexReader reader, String preTag, String postTag) throws IOException, InvalidTokenOffsetsException {

  String fieldLessFieldName = fieldManager.getFieldLessFieldName();

  Query fixedQuery = fixSuperQuery(query, null, fieldLessFieldName);

  Analyzer analyzer = fieldManager.getAnalyzerForQuery();

  SimpleHTMLFormatter htmlFormatter = new SimpleHTMLFormatter(preTag, postTag);
  Document result = new Document();
  for (IndexableField f : document) {
    String name = f.name();
    if (fieldLessFieldName.equals(name) || FIELDS_NOT_TO_HIGHLIGHT.contains(name)) {
      result.add(f);
      continue;
    }
    String text = f.stringValue();
    Number numericValue = f.numericValue();

    Query fieldFixedQuery;
    if (fieldManager.isFieldLessIndexed(name)) {
      fieldFixedQuery = fixSuperQuery(query, name, fieldLessFieldName);
    } else {
      fieldFixedQuery = fixedQuery;
    }

    if (numericValue != null) {
      if (shouldNumberBeHighlighted(name, numericValue, fieldFixedQuery)) {
        String numberHighlight = preTag + text + postTag;
        result.add(new StringField(name, numberHighlight, Store.YES));
      }
    } else {
      Highlighter highlighter = new Highlighter(htmlFormatter, new QueryScorer(fieldFixedQuery, name));
      TokenStream tokenStream = TokenSources.getAnyTokenStream(reader, docId, name, analyzer);
      TextFragment[] frag = highlighter.getBestTextFragments(tokenStream, text, false, 10);
      for (int j = 0; j < frag.length; j++) {
        if ((frag[j] != null) && (frag[j].getScore() > 0)) {
          result.add(new StringField(name, frag[j].toString(), Store.YES));
        }
      }
    }
  }
  return result;
}