| using Lucene.Net.Index; |
| using Lucene.Net.Search; |
| using Lucene.Net.Util; |
| |
| namespace Lucene.Net.Join |
| { |
| /* |
| * 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. |
| */ |
| |
| /// <summary> |
| /// A collector that collects all terms from a specified field matching the query. |
| /// |
| /// @lucene.experimental |
| /// </summary> |
| internal abstract class TermsCollector : ICollector |
| { |
| private readonly string _field; |
| private readonly BytesRefHash _collectorTerms = new BytesRefHash(); |
| |
| internal TermsCollector(string field) |
| { |
| _field = field; |
| } |
| |
| public virtual BytesRefHash CollectorTerms => _collectorTerms; |
| |
| public virtual void SetScorer(Scorer scorer) |
| { |
| } |
| |
| // LUCENENET specific - we need to implement these here, since our abstract base class |
| // is now an interface. |
| |
| /// <summary> |
| /// Called once for every document matching a query, with the unbased document |
| /// number. |
| /// <para/>Note: The collection of the current segment can be terminated by throwing |
| /// a <see cref="CollectionTerminatedException"/>. In this case, the last docs of the |
| /// current <see cref="AtomicReaderContext"/> will be skipped and <see cref="IndexSearcher"/> |
| /// will swallow the exception and continue collection with the next leaf. |
| /// <para/> |
| /// Note: this is called in an inner search loop. For good search performance, |
| /// implementations of this method should not call <see cref="IndexSearcher.Doc(int)"/> or |
| /// <see cref="Lucene.Net.Index.IndexReader.Document(int)"/> on every hit. |
| /// Doing so can slow searches by an order of magnitude or more. |
| /// </summary> |
| public abstract void Collect(int doc); |
| |
| /// <summary> |
| /// Called before collecting from each <see cref="AtomicReaderContext"/>. All doc ids in |
| /// <see cref="Collect(int)"/> will correspond to <see cref="Index.IndexReaderContext.Reader"/>. |
| /// |
| /// Add <see cref="AtomicReaderContext.DocBase"/> to the current <see cref="Index.IndexReaderContext.Reader"/>'s |
| /// internal document id to re-base ids in <see cref="Collect(int)"/>. |
| /// </summary> |
| /// <param name="context">next atomic reader context </param> |
| public abstract void SetNextReader(AtomicReaderContext context); |
| |
| |
| public virtual bool AcceptsDocsOutOfOrder => true; |
| |
| /// <summary> |
| /// Chooses the right <see cref="TermsCollector"/> implementation. |
| /// </summary> |
| /// <param name="field">The field to collect terms for.</param> |
| /// <param name="multipleValuesPerDocument">Whether the field to collect terms for has multiple values per document.</param> |
| /// <returns>A <see cref="TermsCollector"/> instance.</returns> |
| internal static TermsCollector Create(string field, bool multipleValuesPerDocument) |
| { |
| return multipleValuesPerDocument ? (TermsCollector) new MV(field) : new SV(field); |
| } |
| |
| // impl that works with multiple values per document |
| private class MV : TermsCollector |
| { |
| private readonly BytesRef _scratch = new BytesRef(); |
| private SortedSetDocValues _docTermOrds; |
| |
| internal MV(string field) |
| : base(field) |
| { |
| } |
| |
| public override void Collect(int doc) |
| { |
| _docTermOrds.SetDocument(doc); |
| long ord; |
| while ((ord = _docTermOrds.NextOrd()) != SortedSetDocValues.NO_MORE_ORDS) |
| { |
| _docTermOrds.LookupOrd(ord, _scratch); |
| _collectorTerms.Add(_scratch); |
| } |
| } |
| |
| public override void SetNextReader(AtomicReaderContext context) |
| { |
| _docTermOrds = FieldCache.DEFAULT.GetDocTermOrds(context.AtomicReader, _field); |
| } |
| } |
| |
| // impl that works with single value per document |
| private class SV : TermsCollector |
| { |
| private readonly BytesRef _spare = new BytesRef(); |
| private BinaryDocValues _fromDocTerms; |
| |
| internal SV(string field) |
| : base(field) |
| { |
| } |
| |
| public override void Collect(int doc) |
| { |
| _fromDocTerms.Get(doc, _spare); |
| _collectorTerms.Add(_spare); |
| } |
| |
| public override void SetNextReader(AtomicReaderContext context) |
| { |
| _fromDocTerms = FieldCache.DEFAULT.GetTerms(context.AtomicReader, _field, false); |
| } |
| } |
| } |
| } |