/**
* Return a {@link org.apache.lucene.search.highlight.Highlighter} appropriate for this field.
*
* @param query The current Query
* @param fieldName The name of the field
* @param request The current SolrQueryRequest
*/
protected Highlighter getHighlighter(Query query, String fieldName, SolrQueryRequest request) {
SolrParams params = request.getParams();
Highlighter highlighter =
new Highlighter(
getFormatter(fieldName, params),
getEncoder(fieldName, params),
getQueryScorer(query, fieldName, request));
highlighter.setTextFragmenter(getFragmenter(fieldName, params));
return highlighter;
}
/**
* Return a phrase {@link org.apache.lucene.search.highlight.Highlighter} appropriate for this
* field.
*
* @param query The current Query
* @param fieldName The name of the field
* @param request The current SolrQueryRequest
* @param tokenStream document text CachingTokenStream
* @throws IOException If there is a low-level I/O error.
*/
protected Highlighter getPhraseHighlighter(
Query query, String fieldName, SolrQueryRequest request, CachingTokenFilter tokenStream)
throws IOException {
SolrParams params = request.getParams();
Highlighter highlighter = null;
highlighter =
new Highlighter(
getFormatter(fieldName, params),
getEncoder(fieldName, params),
getSpanQueryScorer(query, fieldName, tokenStream, request));
highlighter.setTextFragmenter(getFragmenter(fieldName, params));
return highlighter;
}
private void doHighlightingByHighlighter(
Query query,
SolrQueryRequest req,
NamedList docSummaries,
int docId,
Document doc,
String fieldName)
throws IOException {
final SolrIndexSearcher searcher = req.getSearcher();
final IndexSchema schema = searcher.getSchema();
// TODO: Currently in trunk highlighting numeric fields is broken (Lucene) -
// so we disable them until fixed (see LUCENE-3080)!
// BEGIN: Hack
final SchemaField schemaField = schema.getFieldOrNull(fieldName);
if (schemaField != null
&& ((schemaField.getType() instanceof org.apache.solr.schema.TrieField)
|| (schemaField.getType() instanceof org.apache.solr.schema.TrieDateField))) return;
// END: Hack
SolrParams params = req.getParams();
IndexableField[] docFields = doc.getFields(fieldName);
List<String> listFields = new ArrayList<String>();
for (IndexableField field : docFields) {
listFields.add(field.stringValue());
}
// preserve order of values in a multiValued list
boolean preserveMulti = params.getFieldBool(fieldName, HighlightParams.PRESERVE_MULTI, false);
String[] docTexts = (String[]) listFields.toArray(new String[listFields.size()]);
// according to Document javadoc, doc.getValues() never returns null. check empty instead of
// null
if (docTexts.length == 0) return;
TokenStream tstream = null;
int numFragments = getMaxSnippets(fieldName, params);
boolean mergeContiguousFragments = isMergeContiguousFragments(fieldName, params);
String[] summaries = null;
List<TextFragment> frags = new ArrayList<TextFragment>();
TermOffsetsTokenStream tots = null; // to be non-null iff we're using TermOffsets optimization
TokenStream tvStream =
TokenSources.getTokenStreamWithOffsets(searcher.getIndexReader(), docId, fieldName);
if (tvStream != null) {
tots = new TermOffsetsTokenStream(tvStream);
}
for (int j = 0; j < docTexts.length; j++) {
if (tots != null) {
// if we're using TermOffsets optimization, then get the next
// field value's TokenStream (i.e. get field j's TokenStream) from tots:
tstream = tots.getMultiValuedTokenStream(docTexts[j].length());
} else {
// fall back to analyzer
tstream = createAnalyzerTStream(schema, fieldName, docTexts[j]);
}
int maxCharsToAnalyze =
params.getFieldInt(
fieldName, HighlightParams.MAX_CHARS, Highlighter.DEFAULT_MAX_CHARS_TO_ANALYZE);
Highlighter highlighter;
if (Boolean.valueOf(req.getParams().get(HighlightParams.USE_PHRASE_HIGHLIGHTER, "true"))) {
if (maxCharsToAnalyze < 0) {
tstream = new CachingTokenFilter(tstream);
} else {
tstream = new CachingTokenFilter(new OffsetLimitTokenFilter(tstream, maxCharsToAnalyze));
}
// get highlighter
highlighter = getPhraseHighlighter(query, fieldName, req, (CachingTokenFilter) tstream);
// after highlighter initialization, reset tstream since construction of highlighter already
// used it
tstream.reset();
} else {
// use "the old way"
highlighter = getHighlighter(query, fieldName, req);
}
if (maxCharsToAnalyze < 0) {
highlighter.setMaxDocCharsToAnalyze(docTexts[j].length());
} else {
highlighter.setMaxDocCharsToAnalyze(maxCharsToAnalyze);
}
try {
TextFragment[] bestTextFragments =
highlighter.getBestTextFragments(
tstream, docTexts[j], mergeContiguousFragments, numFragments);
for (int k = 0; k < bestTextFragments.length; k++) {
if (preserveMulti) {
if (bestTextFragments[k] != null) {
frags.add(bestTextFragments[k]);
}
} else {
if ((bestTextFragments[k] != null) && (bestTextFragments[k].getScore() > 0)) {
frags.add(bestTextFragments[k]);
}
}
}
} catch (InvalidTokenOffsetsException e) {
throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, e);
}
}
// sort such that the fragments with the highest score come first
if (!preserveMulti) {
Collections.sort(
frags,
new Comparator<TextFragment>() {
@Override
public int compare(TextFragment arg0, TextFragment arg1) {
return Math.round(arg1.getScore() - arg0.getScore());
}
});
}
// convert fragments back into text
// TODO: we can include score and position information in output as snippet attributes
if (frags.size() > 0) {
ArrayList<String> fragTexts = new ArrayList<String>();
for (TextFragment fragment : frags) {
if (preserveMulti) {
if (fragment != null) {
fragTexts.add(fragment.toString());
}
} else {
if ((fragment != null) && (fragment.getScore() > 0)) {
fragTexts.add(fragment.toString());
}
}
if (fragTexts.size() >= numFragments && !preserveMulti) break;
}
summaries = fragTexts.toArray(new String[0]);
if (summaries.length > 0) docSummaries.add(fieldName, summaries);
}
// no summeries made, copy text from alternate field
if (summaries == null || summaries.length == 0) {
alternateField(docSummaries, params, doc, fieldName);
}
}