| // Lucene version compatibility level 4.8.1 |
| using Lucene.Net.Index; |
| using Lucene.Net.Queries.Function.DocValues; |
| using Lucene.Net.Search; |
| using Lucene.Net.Search.Similarities; |
| using System; |
| using System.Collections; |
| |
| 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="TFIDFSimilarity.DecodeNormValue(long)"/> |
| /// for every document. |
| /// <para/> |
| /// Note that the configured Similarity for the field must be |
| /// a subclass of <see cref="TFIDFSimilarity"/> |
| /// @lucene.internal |
| /// </summary> |
| public class NormValueSource : ValueSource |
| { |
| protected readonly string m_field; |
| |
| public NormValueSource(string field) |
| { |
| this.m_field = field; |
| } |
| |
| public virtual string Name => "norm"; |
| |
| public override string GetDescription() |
| { |
| return Name + '(' + m_field + ')'; |
| } |
| |
| public override void CreateWeight(IDictionary context, IndexSearcher searcher) |
| { |
| context["searcher"] = searcher; |
| } |
| |
| public override FunctionValues GetValues(IDictionary context, AtomicReaderContext readerContext) |
| { |
| var searcher = (IndexSearcher)context["searcher"]; |
| TFIDFSimilarity similarity = IDFValueSource.AsTFIDF(searcher.Similarity, m_field); |
| if (similarity == null) |
| { |
| throw new NotSupportedException("requires a TFIDFSimilarity (such as DefaultSimilarity)"); |
| } |
| |
| NumericDocValues norms = readerContext.AtomicReader.GetNormValues(m_field); |
| if (norms == null) |
| { |
| return new ConstDoubleDocValues(0.0, this); |
| } |
| |
| return new SingleDocValuesAnonymousClass(this, similarity, norms); |
| } |
| |
| private class SingleDocValuesAnonymousClass : SingleDocValues |
| { |
| private readonly TFIDFSimilarity similarity; |
| private readonly NumericDocValues norms; |
| |
| public SingleDocValuesAnonymousClass(NormValueSource @this, TFIDFSimilarity similarity, NumericDocValues norms) |
| : base(@this) |
| { |
| this.similarity = similarity; |
| this.norms = norms; |
| } |
| |
| /// <summary> |
| /// NOTE: This was floatVal() in Lucene |
| /// </summary> |
| public override float SingleVal(int doc) |
| { |
| return similarity.DecodeNormValue(norms.Get(doc)); |
| } |
| } |
| |
| public override bool Equals(object o) |
| { |
| if (this.GetType() != o.GetType()) |
| { |
| return false; |
| } |
| return this.m_field.Equals(((NormValueSource)o).m_field, StringComparison.Ordinal); |
| } |
| |
| public override int GetHashCode() |
| { |
| return this.GetType().GetHashCode() + m_field.GetHashCode(); |
| } |
| } |
| } |