private void process(int groupOrd, int facetOrd) {
      if (facetOrd < startFacetOrd || facetOrd >= endFacetOrd) {
        return;
      }

      int segmentGroupedFacetsIndex = groupOrd * (facetFieldNumTerms + 1) + facetOrd;
      if (segmentGroupedFacetHits.exists(segmentGroupedFacetsIndex)) {
        return;
      }

      segmentTotalCount++;
      segmentFacetCounts[facetOrd]++;

      segmentGroupedFacetHits.put(segmentGroupedFacetsIndex);

      BytesRef groupKey;
      if (groupOrd == -1) {
        groupKey = null;
      } else {
        groupKey = BytesRef.deepCopyOf(groupFieldTermsIndex.lookupOrd(groupOrd));
      }

      final BytesRef facetValue;
      if (facetOrd == facetFieldNumTerms) {
        facetValue = null;
      } else {
        facetValue = BytesRef.deepCopyOf(facetFieldDocTermOrds.lookupOrd(facetOrd));
      }
      groupedFacetHits.add(new GroupedFacetHit(groupKey, facetValue));
    }
 @Override
 public void collect(int doc) throws IOException {
   docTermOrds.setDocument(doc);
   long ord;
   while ((ord = docTermOrds.nextOrd()) != SortedSetDocValues.NO_MORE_ORDS) {
     final BytesRef term = docTermOrds.lookupOrd(ord);
     collectorTerms.add(term);
   }
 }
  public void testDocValuesMemoryIndexVsNormalIndex() throws Exception {
    Document doc = new Document();
    long randomLong = random().nextLong();
    doc.add(new NumericDocValuesField("numeric", randomLong));
    if (random().nextBoolean()) {
      doc.add(new LegacyLongField("numeric", randomLong, Field.Store.NO));
    }
    int numValues = atLeast(5);
    for (int i = 0; i < numValues; i++) {
      randomLong = random().nextLong();
      doc.add(new SortedNumericDocValuesField("sorted_numeric", randomLong));
      if (random().nextBoolean()) {
        // randomly duplicate field/value
        doc.add(new SortedNumericDocValuesField("sorted_numeric", randomLong));
      }
      if (random().nextBoolean()) {
        doc.add(new LegacyLongField("numeric", randomLong, Field.Store.NO));
      }
    }
    BytesRef randomTerm = new BytesRef(randomTerm());
    doc.add(new BinaryDocValuesField("binary", randomTerm));
    if (random().nextBoolean()) {
      doc.add(new StringField("binary", randomTerm, Field.Store.NO));
    }
    randomTerm = new BytesRef(randomTerm());
    doc.add(new SortedDocValuesField("sorted", randomTerm));
    if (random().nextBoolean()) {
      doc.add(new StringField("sorted", randomTerm, Field.Store.NO));
    }
    numValues = atLeast(5);
    for (int i = 0; i < numValues; i++) {
      randomTerm = new BytesRef(randomTerm());
      doc.add(new SortedSetDocValuesField("sorted_set", randomTerm));
      if (random().nextBoolean()) {
        // randomly duplicate field/value
        doc.add(new SortedSetDocValuesField("sorted_set", randomTerm));
      }
      if (random().nextBoolean()) {
        // randomily just add a normal string field
        doc.add(new StringField("sorted_set", randomTerm, Field.Store.NO));
      }
    }

    MockAnalyzer mockAnalyzer = new MockAnalyzer(random());
    MemoryIndex memoryIndex = MemoryIndex.fromDocument(doc, mockAnalyzer);
    IndexReader indexReader = memoryIndex.createSearcher().getIndexReader();
    LeafReader leafReader = indexReader.leaves().get(0).reader();

    Directory dir = newDirectory();
    IndexWriter writer = new IndexWriter(dir, newIndexWriterConfig(random(), mockAnalyzer));
    writer.addDocument(doc);
    writer.close();
    IndexReader controlIndexReader = DirectoryReader.open(dir);
    LeafReader controlLeafReader = controlIndexReader.leaves().get(0).reader();

    NumericDocValues numericDocValues = leafReader.getNumericDocValues("numeric");
    NumericDocValues controlNumericDocValues = controlLeafReader.getNumericDocValues("numeric");
    assertEquals(controlNumericDocValues.get(0), numericDocValues.get(0));

    SortedNumericDocValues sortedNumericDocValues =
        leafReader.getSortedNumericDocValues("sorted_numeric");
    sortedNumericDocValues.setDocument(0);
    SortedNumericDocValues controlSortedNumericDocValues =
        controlLeafReader.getSortedNumericDocValues("sorted_numeric");
    controlSortedNumericDocValues.setDocument(0);
    assertEquals(controlSortedNumericDocValues.count(), sortedNumericDocValues.count());
    for (int i = 0; i < controlSortedNumericDocValues.count(); i++) {
      assertEquals(controlSortedNumericDocValues.valueAt(i), sortedNumericDocValues.valueAt(i));
    }

    BinaryDocValues binaryDocValues = leafReader.getBinaryDocValues("binary");
    BinaryDocValues controlBinaryDocValues = controlLeafReader.getBinaryDocValues("binary");
    assertEquals(controlBinaryDocValues.get(0), binaryDocValues.get(0));

    SortedDocValues sortedDocValues = leafReader.getSortedDocValues("sorted");
    SortedDocValues controlSortedDocValues = controlLeafReader.getSortedDocValues("sorted");
    assertEquals(controlSortedDocValues.getValueCount(), sortedDocValues.getValueCount());
    assertEquals(controlSortedDocValues.get(0), sortedDocValues.get(0));
    assertEquals(controlSortedDocValues.getOrd(0), sortedDocValues.getOrd(0));
    assertEquals(controlSortedDocValues.lookupOrd(0), sortedDocValues.lookupOrd(0));

    SortedSetDocValues sortedSetDocValues = leafReader.getSortedSetDocValues("sorted_set");
    sortedSetDocValues.setDocument(0);
    SortedSetDocValues controlSortedSetDocValues =
        controlLeafReader.getSortedSetDocValues("sorted_set");
    controlSortedSetDocValues.setDocument(0);
    assertEquals(controlSortedSetDocValues.getValueCount(), sortedSetDocValues.getValueCount());
    for (long controlOrd = controlSortedSetDocValues.nextOrd();
        controlOrd != SortedSetDocValues.NO_MORE_ORDS;
        controlOrd = controlSortedSetDocValues.nextOrd()) {
      assertEquals(controlOrd, sortedSetDocValues.nextOrd());
      assertEquals(
          controlSortedSetDocValues.lookupOrd(controlOrd),
          sortedSetDocValues.lookupOrd(controlOrd));
    }
    assertEquals(SortedSetDocValues.NO_MORE_ORDS, sortedSetDocValues.nextOrd());

    indexReader.close();
    controlIndexReader.close();
    dir.close();
  }
  public static NamedList<Integer> getCounts(
      SolrIndexSearcher searcher,
      DocSet docs,
      String fieldName,
      int offset,
      int limit,
      int mincount,
      boolean missing,
      String sort,
      String prefix)
      throws IOException {
    SchemaField schemaField = searcher.getSchema().getField(fieldName);
    FieldType ft = schemaField.getType();
    NamedList<Integer> res = new NamedList<Integer>();

    final SortedSetDocValues si; // for term lookups only
    OrdinalMap ordinalMap = null; // for mapping per-segment ords to global ones
    if (schemaField.multiValued()) {
      si = searcher.getAtomicReader().getSortedSetDocValues(fieldName);
      if (si instanceof MultiSortedSetDocValues) {
        ordinalMap = ((MultiSortedSetDocValues) si).mapping;
      }
    } else {
      SortedDocValues single = searcher.getAtomicReader().getSortedDocValues(fieldName);
      si = single == null ? null : new SingletonSortedSetDocValues(single);
      if (single instanceof MultiSortedDocValues) {
        ordinalMap = ((MultiSortedDocValues) single).mapping;
      }
    }
    if (si == null) {
      return finalize(res, searcher, schemaField, docs, -1, missing);
    }
    if (si.getValueCount() >= Integer.MAX_VALUE) {
      throw new UnsupportedOperationException(
          "Currently this faceting method is limited to " + Integer.MAX_VALUE + " unique terms");
    }

    final BytesRef br = new BytesRef();

    final BytesRef prefixRef;
    if (prefix == null) {
      prefixRef = null;
    } else if (prefix.length() == 0) {
      prefix = null;
      prefixRef = null;
    } else {
      prefixRef = new BytesRef(prefix);
    }

    int startTermIndex, endTermIndex;
    if (prefix != null) {
      startTermIndex = (int) si.lookupTerm(prefixRef);
      if (startTermIndex < 0) startTermIndex = -startTermIndex - 1;
      prefixRef.append(UnicodeUtil.BIG_TERM);
      endTermIndex = (int) si.lookupTerm(prefixRef);
      assert endTermIndex < 0;
      endTermIndex = -endTermIndex - 1;
    } else {
      startTermIndex = -1;
      endTermIndex = (int) si.getValueCount();
    }

    final int nTerms = endTermIndex - startTermIndex;
    int missingCount = -1;
    final CharsRef charsRef = new CharsRef(10);
    if (nTerms > 0 && docs.size() >= mincount) {

      // count collection array only needs to be as big as the number of terms we are
      // going to collect counts for.
      final int[] counts = new int[nTerms];

      Filter filter = docs.getTopFilter();
      List<AtomicReaderContext> leaves = searcher.getTopReaderContext().leaves();
      for (int subIndex = 0; subIndex < leaves.size(); subIndex++) {
        AtomicReaderContext leaf = leaves.get(subIndex);
        DocIdSet dis =
            filter.getDocIdSet(leaf, null); // solr docsets already exclude any deleted docs
        DocIdSetIterator disi = null;
        if (dis != null) {
          disi = dis.iterator();
        }
        if (disi != null) {
          if (schemaField.multiValued()) {
            SortedSetDocValues sub = leaf.reader().getSortedSetDocValues(fieldName);
            if (sub == null) {
              sub = SortedSetDocValues.EMPTY;
            }
            if (sub instanceof SingletonSortedSetDocValues) {
              // some codecs may optimize SORTED_SET storage for single-valued fields
              final SortedDocValues values =
                  ((SingletonSortedSetDocValues) sub).getSortedDocValues();
              accumSingle(counts, startTermIndex, values, disi, subIndex, ordinalMap);
            } else {
              accumMulti(counts, startTermIndex, sub, disi, subIndex, ordinalMap);
            }
          } else {
            SortedDocValues sub = leaf.reader().getSortedDocValues(fieldName);
            if (sub == null) {
              sub = SortedDocValues.EMPTY;
            }
            accumSingle(counts, startTermIndex, sub, disi, subIndex, ordinalMap);
          }
        }
      }

      if (startTermIndex == -1) {
        missingCount = counts[0];
      }

      // IDEA: we could also maintain a count of "other"... everything that fell outside
      // of the top 'N'

      int off = offset;
      int lim = limit >= 0 ? limit : Integer.MAX_VALUE;

      if (sort.equals(FacetParams.FACET_SORT_COUNT)
          || sort.equals(FacetParams.FACET_SORT_COUNT_LEGACY)) {
        int maxsize = limit > 0 ? offset + limit : Integer.MAX_VALUE - 1;
        maxsize = Math.min(maxsize, nTerms);
        LongPriorityQueue queue =
            new LongPriorityQueue(Math.min(maxsize, 1000), maxsize, Long.MIN_VALUE);

        int min = mincount - 1; // the smallest value in the top 'N' values
        for (int i = (startTermIndex == -1) ? 1 : 0; i < nTerms; i++) {
          int c = counts[i];
          if (c > min) {
            // NOTE: we use c>min rather than c>=min as an optimization because we are going in
            // index order, so we already know that the keys are ordered.  This can be very
            // important if a lot of the counts are repeated (like zero counts would be).

            // smaller term numbers sort higher, so subtract the term number instead
            long pair = (((long) c) << 32) + (Integer.MAX_VALUE - i);
            boolean displaced = queue.insert(pair);
            if (displaced) min = (int) (queue.top() >>> 32);
          }
        }

        // if we are deep paging, we don't have to order the highest "offset" counts.
        int collectCount = Math.max(0, queue.size() - off);
        assert collectCount <= lim;

        // the start and end indexes of our list "sorted" (starting with the highest value)
        int sortedIdxStart = queue.size() - (collectCount - 1);
        int sortedIdxEnd = queue.size() + 1;
        final long[] sorted = queue.sort(collectCount);

        for (int i = sortedIdxStart; i < sortedIdxEnd; i++) {
          long pair = sorted[i];
          int c = (int) (pair >>> 32);
          int tnum = Integer.MAX_VALUE - (int) pair;
          si.lookupOrd(startTermIndex + tnum, br);
          ft.indexedToReadable(br, charsRef);
          res.add(charsRef.toString(), c);
        }

      } else {
        // add results in index order
        int i = (startTermIndex == -1) ? 1 : 0;
        if (mincount <= 0) {
          // if mincount<=0, then we won't discard any terms and we know exactly
          // where to start.
          i += off;
          off = 0;
        }

        for (; i < nTerms; i++) {
          int c = counts[i];
          if (c < mincount || --off >= 0) continue;
          if (--lim < 0) break;
          si.lookupOrd(startTermIndex + i, br);
          ft.indexedToReadable(br, charsRef);
          res.add(charsRef.toString(), c);
        }
      }
    }

    return finalize(res, searcher, schemaField, docs, missingCount, missing);
  }