@Override public void collect(int doc) throws IOException { if (doc > groupFieldTermsIndex.docID()) { groupFieldTermsIndex.advance(doc); } int groupOrd; if (doc == groupFieldTermsIndex.docID()) { groupOrd = groupFieldTermsIndex.ordValue(); } else { groupOrd = -1; } if (facetFieldNumTerms == 0) { int segmentGroupedFacetsIndex = groupOrd * (facetFieldNumTerms + 1); if (facetPrefix != null || segmentGroupedFacetHits.exists(segmentGroupedFacetsIndex)) { return; } segmentTotalCount++; segmentFacetCounts[facetFieldNumTerms]++; segmentGroupedFacetHits.put(segmentGroupedFacetsIndex); BytesRef groupKey; if (groupOrd == -1) { groupKey = null; } else { groupKey = BytesRef.deepCopyOf(groupFieldTermsIndex.lookupOrd(groupOrd)); } groupedFacetHits.add(new GroupedFacetHit(groupKey, null)); return; } if (doc > facetFieldDocTermOrds.docID()) { facetFieldDocTermOrds.advance(doc); } boolean empty = true; if (doc == facetFieldDocTermOrds.docID()) { long ord; while ((ord = facetFieldDocTermOrds.nextOrd()) != SortedSetDocValues.NO_MORE_ORDS) { process(groupOrd, (int) ord); empty = false; } } if (empty) { process( groupOrd, facetFieldNumTerms); // this facet ord is reserved for docs not containing facet field. } }