| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.lucene.search.join; |
| |
| import java.io.IOException; |
| |
| import org.apache.lucene.index.BinaryDocValues; |
| import org.apache.lucene.index.SortedSetDocValues; |
| import org.apache.lucene.util.BytesRef; |
| import org.apache.lucene.util.BytesRefHash; |
| |
| /** |
| * A collector that collects all terms from a specified field matching the query. |
| * |
| * @lucene.experimental |
| */ |
| abstract class TermsCollector<DV> extends DocValuesTermsCollector<DV> { |
| |
| TermsCollector(Function<DV> docValuesCall) { |
| super(docValuesCall); |
| } |
| |
| final BytesRefHash collectorTerms = new BytesRefHash(); |
| |
| public BytesRefHash getCollectorTerms() { |
| return collectorTerms; |
| } |
| |
| /** |
| * Chooses the right {@link TermsCollector} implementation. |
| * |
| * @param field The field to collect terms for |
| * @param multipleValuesPerDocument Whether the field to collect terms for has multiple values per document. |
| * @return a {@link TermsCollector} instance |
| */ |
| static TermsCollector<?> create(String field, boolean multipleValuesPerDocument) { |
| return multipleValuesPerDocument |
| ? new MV(sortedSetDocValues(field)) |
| : new SV(binaryDocValues(field)); |
| } |
| |
| // impl that works with multiple values per document |
| static class MV extends TermsCollector<SortedSetDocValues> { |
| |
| MV(Function<SortedSetDocValues> docValuesCall) { |
| super(docValuesCall); |
| } |
| |
| @Override |
| public void collect(int doc) throws IOException { |
| long ord; |
| if (doc > docValues.docID()) { |
| docValues.advance(doc); |
| } |
| if (doc == docValues.docID()) { |
| while ((ord = docValues.nextOrd()) != SortedSetDocValues.NO_MORE_ORDS) { |
| final BytesRef term = docValues.lookupOrd(ord); |
| collectorTerms.add(term); |
| } |
| } |
| } |
| } |
| |
| // impl that works with single value per document |
| static class SV extends TermsCollector<BinaryDocValues> { |
| |
| SV(Function<BinaryDocValues> docValuesCall) { |
| super(docValuesCall); |
| } |
| |
| @Override |
| public void collect(int doc) throws IOException { |
| BytesRef term; |
| if (docValues.advanceExact(doc)) { |
| term = docValues.binaryValue(); |
| } else { |
| term = new BytesRef(BytesRef.EMPTY_BYTES); |
| } |
| collectorTerms.add(term); |
| } |
| } |
| |
| @Override |
| public org.apache.lucene.search.ScoreMode scoreMode() { |
| return org.apache.lucene.search.ScoreMode.COMPLETE_NO_SCORES; |
| } |
| } |