pq, int numHits, boolean fillFields) {
+ super(pq);
+ this.numHits = numHits;
+ this.fillFields = fillFields;
+ }
+
+ /**
+ * Creates a new {@link TopFieldCollector} from the given
+ * arguments.
+ *
+ * NOTE: The instances returned by this method
+ * pre-allocate a full array of length
+ * numHits.
+ *
+ * @param sort
+ * the sort criteria (SortFields).
+ * @param numHits
+ * the number of results to collect.
+ * @param fillFields
+ * specifies whether the actual field values should be returned on
+ * the results (FieldDoc).
+ * @param trackDocScores
+ * specifies whether document scores should be tracked and set on the
+ * results. Note that if set to false, then the results' scores will
+ * be set to Float.NaN. Setting this to true affects performance, as
+ * it incurs the score computation on each competitive result.
+ * Therefore if document scores are not required by the application,
+ * it is recommended to set it to false.
+ * @param trackMaxScore
+ * specifies whether the query's maxScore should be tracked and set
+ * on the resulting {@link TopDocs}. Note that if set to false,
+ * {@link TopDocs#getMaxScore()} returns Float.NaN. Setting this to
+ * true affects performance as it incurs the score computation on
+ * each result. Also, setting this true automatically sets
+ * trackDocScores to true as well.
+ * @param docsScoredInOrder
+ * specifies whether documents are scored in doc Id order or not by
+ * the given {@link Scorer} in {@link #setScorer(Scorer)}.
+ * @return a {@link TopFieldCollector} instance which will sort the results by
+ * the sort criteria.
+ * @throws IOException
+ */
+ public static TopFieldCollector create(Sort sort, int numHits,
+ boolean fillFields, boolean trackDocScores, boolean trackMaxScore,
+ boolean docsScoredInOrder)
+ throws IOException {
+ if (sort.fields.length == 0) {
+ throw new IllegalArgumentException("Sort must contain at least one field");
+ }
+
+ if (numHits <= 0) {
+ throw new IllegalArgumentException("numHits must be > 0; please use TotalHitCountCollector if you just need the total hit count");
+ }
+
+ FieldValueHitQueue queue = FieldValueHitQueue.create(sort.fields, numHits);
+ if (queue.getComparators().length == 1) {
+ if (docsScoredInOrder) {
+ if (trackMaxScore) {
+ return new OneComparatorScoringMaxScoreCollector(queue, numHits, fillFields);
+ } else if (trackDocScores) {
+ return new OneComparatorScoringNoMaxScoreCollector(queue, numHits, fillFields);
+ } else {
+ return new OneComparatorNonScoringCollector(queue, numHits, fillFields);
+ }
+ } else {
+ if (trackMaxScore) {
+ return new OutOfOrderOneComparatorScoringMaxScoreCollector(queue, numHits, fillFields);
+ } else if (trackDocScores) {
+ return new OutOfOrderOneComparatorScoringNoMaxScoreCollector(queue, numHits, fillFields);
+ } else {
+ return new OutOfOrderOneComparatorNonScoringCollector(queue, numHits, fillFields);
+ }
+ }
+ }
+
+ // multiple comparators.
+ if (docsScoredInOrder) {
+ if (trackMaxScore) {
+ return new MultiComparatorScoringMaxScoreCollector(queue, numHits, fillFields);
+ } else if (trackDocScores) {
+ return new MultiComparatorScoringNoMaxScoreCollector(queue, numHits, fillFields);
+ } else {
+ return new MultiComparatorNonScoringCollector(queue, numHits, fillFields);
+ }
+ } else {
+ if (trackMaxScore) {
+ return new OutOfOrderMultiComparatorScoringMaxScoreCollector(queue, numHits, fillFields);
+ } else if (trackDocScores) {
+ return new OutOfOrderMultiComparatorScoringNoMaxScoreCollector(queue, numHits, fillFields);
+ } else {
+ return new OutOfOrderMultiComparatorNonScoringCollector(queue, numHits, fillFields);
+ }
+ }
+ }
+
+ final void add(int slot, int doc, float score) {
+ bottom = pq.add(new Entry(slot, docBase + doc, score));
+ queueFull = totalHits == numHits;
+ }
+
+ /*
+ * Only the following callback methods need to be overridden since
+ * topDocs(int, int) calls them to return the results.
+ */
+
+ @Override
+ protected void populateResults(ScoreDoc[] results, int howMany) {
+ if (fillFields) {
+ // avoid casting if unnecessary.
+ FieldValueHitQueue queue = (FieldValueHitQueue) pq;
+ for (int i = howMany - 1; i >= 0; i--) {
+ results[i] = queue.fillFields(queue.pop());
+ }
+ } else {
+ for (int i = howMany - 1; i >= 0; i--) {
+ Entry entry = pq.pop();
+ results[i] = new FieldDoc(entry.doc, entry.score);
+ }
+ }
+ }
+
+ @Override
+ protected TopDocs newTopDocs(ScoreDoc[] results, int start) {
+ if (results == null) {
+ results = EMPTY_SCOREDOCS;
+ // Set maxScore to NaN, in case this is a maxScore tracking collector.
+ maxScore = Float.NaN;
+ }
+
+ // If this is a maxScoring tracking collector and there were no results,
+ return new TopFieldDocs(totalHits, results, ((FieldValueHitQueue) pq).getFields(), maxScore);
+ }
+
+ @Override
+ public boolean acceptsDocsOutOfOrder() {
+ return false;
+ }
+}