| using Lucene.Net.Index; |
| using Lucene.Net.Queries.Function.DocValues; |
| using Lucene.Net.Search; |
| using Lucene.Net.Util; |
| using System; |
| using System.Collections; |
| using System.IO; |
| |
| namespace Lucene.Net.Queries.Function.ValueSources |
| { |
| /* |
| * 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> |
| /// Function that returns <see cref="DocsEnum.Freq"/> for the |
| /// supplied term in every document. |
| /// <para/> |
| /// If the term does not exist in the document, returns 0. |
| /// If frequencies are omitted, returns 1. |
| /// </summary> |
| public class TermFreqValueSource : DocFreqValueSource |
| { |
| public TermFreqValueSource(string field, string val, string indexedField, BytesRef indexedBytes) |
| : base(field, val, indexedField, indexedBytes) |
| { |
| } |
| |
| public override string Name => "termfreq"; |
| |
| public override FunctionValues GetValues(IDictionary context, AtomicReaderContext readerContext) |
| { |
| Fields fields = readerContext.AtomicReader.Fields; |
| Terms terms = fields.GetTerms(m_indexedField); |
| |
| return new Int32DocValuesAnonymousInnerClassHelper(this, this, terms); |
| } |
| |
| private class Int32DocValuesAnonymousInnerClassHelper : Int32DocValues |
| { |
| private readonly TermFreqValueSource outerInstance; |
| |
| private readonly Terms terms; |
| |
| public Int32DocValuesAnonymousInnerClassHelper(TermFreqValueSource outerInstance, TermFreqValueSource @this, Terms terms) |
| : base(@this) |
| { |
| this.outerInstance = outerInstance; |
| this.terms = terms; |
| lastDocRequested = -1; |
| Reset(); |
| } |
| |
| private DocsEnum docs; |
| private int atDoc; |
| private int lastDocRequested; |
| |
| public virtual void Reset() |
| { |
| // no one should call us for deleted docs? |
| |
| if (terms != null) |
| { |
| TermsEnum termsEnum = terms.GetEnumerator(); |
| if (termsEnum.SeekExact(outerInstance.m_indexedBytes)) |
| { |
| docs = termsEnum.Docs(null, null); |
| } |
| else |
| { |
| docs = null; |
| } |
| } |
| else |
| { |
| docs = null; |
| } |
| |
| if (docs == null) |
| { |
| docs = new DocsEnumAnonymousInnerClassHelper(); |
| } |
| atDoc = -1; |
| } |
| |
| private class DocsEnumAnonymousInnerClassHelper : DocsEnum |
| { |
| public override int Freq => 0; |
| |
| public override int DocID => DocIdSetIterator.NO_MORE_DOCS; |
| |
| public override int NextDoc() |
| { |
| return DocIdSetIterator.NO_MORE_DOCS; |
| } |
| |
| public override int Advance(int target) |
| { |
| return DocIdSetIterator.NO_MORE_DOCS; |
| } |
| |
| public override long GetCost() |
| { |
| return 0; |
| } |
| } |
| |
| /// <summary> |
| /// NOTE: This was intVal() in Lucene |
| /// </summary> |
| public override int Int32Val(int doc) |
| { |
| try |
| { |
| if (doc < lastDocRequested) |
| { |
| // out-of-order access.... reset |
| Reset(); |
| } |
| lastDocRequested = doc; |
| |
| if (atDoc < doc) |
| { |
| atDoc = docs.Advance(doc); |
| } |
| |
| if (atDoc > doc) |
| { |
| // term doesn't match this document... either because we hit the |
| // end, or because the next doc is after this doc. |
| return 0; |
| } |
| |
| // a match! |
| return docs.Freq; |
| } |
| catch (IOException e) |
| { |
| throw new Exception("caught exception in function " + outerInstance.GetDescription() + " : doc=" + doc, e); |
| } |
| } |
| } |
| } |
| } |