src/Lucene.Net/Search/TermQuery.cs - lucenenet - Git at Google

 using Lucene.Net.Diagnostics;
 using System;
 using System.Collections.Generic;
 using System.Text;

 namespace Lucene.Net.Search
 {
     /*
      * 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.
      */

     using AtomicReader = Lucene.Net.Index.AtomicReader;
     using AtomicReaderContext = Lucene.Net.Index.AtomicReaderContext;
     using DocsEnum = Lucene.Net.Index.DocsEnum;
     using IBits = Lucene.Net.Util.IBits;
     using IndexReaderContext = Lucene.Net.Index.IndexReaderContext;
     using ReaderUtil = Lucene.Net.Index.ReaderUtil;
     using Similarity = Lucene.Net.Search.Similarities.Similarity;
     using SimScorer = Lucene.Net.Search.Similarities.Similarity.SimScorer;
     using Term = Lucene.Net.Index.Term;
     using TermContext = Lucene.Net.Index.TermContext;
     using TermsEnum = Lucene.Net.Index.TermsEnum;
     using TermState = Lucene.Net.Index.TermState;
     using ToStringUtils = Lucene.Net.Util.ToStringUtils;

     /// <summary>
     /// A <see cref="Query"/> that matches documents containing a term.
     /// this may be combined with other terms with a <see cref="BooleanQuery"/>.
     /// </summary>
 #if FEATURE_SERIALIZABLE
     [Serializable]
 #endif
     public class TermQuery : Query
     {
         private readonly Term term;
         private readonly int docFreq;
         private readonly TermContext perReaderTermState;

         internal sealed class TermWeight : Weight
         {
             private readonly TermQuery outerInstance;

             internal readonly Similarity similarity;
             internal readonly Similarity.SimWeight stats;
             internal readonly TermContext termStates;

             public TermWeight(TermQuery outerInstance, IndexSearcher searcher, TermContext termStates)
             {
                 this.outerInstance = outerInstance;
                 if (Debugging.AssertsEnabled) Debugging.Assert(termStates != null, "TermContext must not be null");
                 this.termStates = termStates;
                 this.similarity = searcher.Similarity;
                 this.stats = similarity.ComputeWeight(outerInstance.Boost, searcher.CollectionStatistics(outerInstance.term.Field), searcher.TermStatistics(outerInstance.term, termStates));
             }

             public override string ToString()
             {
                 return "weight(" + outerInstance + ")";
             }

             public override Query Query => outerInstance;

             public override float GetValueForNormalization()
             {
                 return stats.GetValueForNormalization();
             }

             public override void Normalize(float queryNorm, float topLevelBoost)
             {
                 stats.Normalize(queryNorm, topLevelBoost);
             }

             public override Scorer GetScorer(AtomicReaderContext context, IBits acceptDocs)
             {
                 if (Debugging.AssertsEnabled) Debugging.Assert(termStates.TopReaderContext == ReaderUtil.GetTopLevelContext(context), () => "The top-reader used to create Weight (" + termStates.TopReaderContext + ") is not the same as the current reader's top-reader (" + ReaderUtil.GetTopLevelContext(context));
                 TermsEnum termsEnum = GetTermsEnum(context);
                 if (termsEnum == null)
                 {
                     return null;
                 }
                 DocsEnum docs = termsEnum.Docs(acceptDocs, null);
                 if (Debugging.AssertsEnabled) Debugging.Assert(docs != null);
                 return new TermScorer(this, docs, similarity.GetSimScorer(stats, context));
             }

             /// <summary>
             /// Returns a <see cref="TermsEnum"/> positioned at this weights <see cref="Index.Term"/> or <c>null</c> if
             /// the term does not exist in the given context.
             /// </summary>
             private TermsEnum GetTermsEnum(AtomicReaderContext context)
             {
                 TermState state = termStates.Get(context.Ord);
                 if (state == null) // term is not present in that reader
                 {
                     if (Debugging.AssertsEnabled) Debugging.Assert(TermNotInReader(context.AtomicReader, outerInstance.term), () => "no termstate found but term exists in reader term=" + outerInstance.term);
                     return null;
                 }
                 //System.out.println("LD=" + reader.getLiveDocs() + " set?=" + (reader.getLiveDocs() != null ? reader.getLiveDocs().get(0) : "null"));
                 TermsEnum termsEnum = context.AtomicReader.GetTerms(outerInstance.term.Field).GetEnumerator();
                 termsEnum.SeekExact(outerInstance.term.Bytes, state);
                 return termsEnum;
             }

             private bool TermNotInReader(AtomicReader reader, Term term)
             {
                 // only called from assert
                 //System.out.println("TQ.termNotInReader reader=" + reader + " term=" + field + ":" + bytes.utf8ToString());
                 return reader.DocFreq(term) == 0;
             }

             public override Explanation Explain(AtomicReaderContext context, int doc)
             {
                 Scorer scorer = GetScorer(context, context.AtomicReader.LiveDocs);
                 if (scorer != null)
                 {
                     int newDoc = scorer.Advance(doc);
                     if (newDoc == doc)
                     {
                         float freq = scorer.Freq;
                         SimScorer docScorer = similarity.GetSimScorer(stats, context);
                         ComplexExplanation result = new ComplexExplanation();
                         result.Description = "weight(" + Query + " in " + doc + ") [" + similarity.GetType().Name + "], result of:";
                         Explanation scoreExplanation = docScorer.Explain(doc, new Explanation(freq, "termFreq=" + freq));
                         result.AddDetail(scoreExplanation);
                         result.Value = scoreExplanation.Value;
                         result.Match = true;
                         return result;
                     }
                 }
                 return new ComplexExplanation(false, 0.0f, "no matching term");
             }
         }

         /// <summary>
         /// Constructs a query for the term <paramref name="t"/>. </summary>
         public TermQuery(Term t)
             : this(t, -1)
         {
         }

         /// <summary>
         /// Expert: constructs a <see cref="TermQuery"/> that will use the
         /// provided <paramref name="docFreq"/> instead of looking up the docFreq
         /// against the searcher.
         /// </summary>
         public TermQuery(Term t, int docFreq)
         {
             term = t;
             this.docFreq = docFreq;
             perReaderTermState = null;
         }

         /// <summary>
         /// Expert: constructs a <see cref="TermQuery"/> that will use the
         /// provided docFreq instead of looking up the docFreq
         /// against the searcher.
         /// </summary>
         public TermQuery(Term t, TermContext states)
         {
             if (Debugging.AssertsEnabled) Debugging.Assert(states != null);
             term = t;
             docFreq = states.DocFreq;
             perReaderTermState = states;
         }

         /// <summary>
         /// Returns the term of this query. </summary>
         public virtual Term Term => term;

         public override Weight CreateWeight(IndexSearcher searcher)
         {
             IndexReaderContext context = searcher.TopReaderContext;
             TermContext termState;
             if (perReaderTermState == null || perReaderTermState.TopReaderContext != context)
             {
                 // make TermQuery single-pass if we don't have a PRTS or if the context differs!
                 termState = TermContext.Build(context, term);
             }
             else
             {
                 // PRTS was pre-build for this IS
                 termState = this.perReaderTermState;
             }

             // we must not ignore the given docFreq - if set use the given value (lie)
             if (docFreq != -1)
             {
                 termState.DocFreq = docFreq;
             }

             return new TermWeight(this, searcher, termState);
         }

         public override void ExtractTerms(ISet<Term> terms)
         {
             terms.Add(Term);
         }

         /// <summary>
         /// Prints a user-readable version of this query. </summary>
         public override string ToString(string field)
         {
             StringBuilder buffer = new StringBuilder();
             if (!term.Field.Equals(field, StringComparison.Ordinal))
             {
                 buffer.Append(term.Field);
                 buffer.Append(":");
             }
             buffer.Append(term.Text());
             buffer.Append(ToStringUtils.Boost(Boost));
             return buffer.ToString();
         }

         /// <summary>
         /// Returns <c>true</c> if <paramref name="o"/> is equal to this. </summary>
         public override bool Equals(object o)
         {
             if (!(o is TermQuery))
             {
                 return false;
             }
             TermQuery other = (TermQuery)o;
             return (this.Boost == other.Boost) && this.term.Equals(other.term);
         }

         /// <summary>
         /// Returns a hash code value for this object. </summary>
         public override int GetHashCode()
         {
             return J2N.BitConversion.SingleToInt32Bits(Boost) ^ term.GetHashCode();
         }
     }
 }
	using Lucene.Net.Diagnostics;
	using System;
	using System.Collections.Generic;
	using System.Text;

	namespace Lucene.Net.Search
	{
	/*
	* 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.
	*/

	using AtomicReader = Lucene.Net.Index.AtomicReader;
	using AtomicReaderContext = Lucene.Net.Index.AtomicReaderContext;
	using DocsEnum = Lucene.Net.Index.DocsEnum;
	using IBits = Lucene.Net.Util.IBits;
	using IndexReaderContext = Lucene.Net.Index.IndexReaderContext;
	using ReaderUtil = Lucene.Net.Index.ReaderUtil;
	using Similarity = Lucene.Net.Search.Similarities.Similarity;
	using SimScorer = Lucene.Net.Search.Similarities.Similarity.SimScorer;
	using Term = Lucene.Net.Index.Term;
	using TermContext = Lucene.Net.Index.TermContext;
	using TermsEnum = Lucene.Net.Index.TermsEnum;
	using TermState = Lucene.Net.Index.TermState;
	using ToStringUtils = Lucene.Net.Util.ToStringUtils;

	/// <summary>
	/// A <see cref="Query"/> that matches documents containing a term.
	/// this may be combined with other terms with a <see cref="BooleanQuery"/>.
	/// </summary>
	#if FEATURE_SERIALIZABLE
	[Serializable]
	#endif
	public class TermQuery : Query
	{
	private readonly Term term;
	private readonly int docFreq;
	private readonly TermContext perReaderTermState;

	internal sealed class TermWeight : Weight
	{
	private readonly TermQuery outerInstance;

	internal readonly Similarity similarity;
	internal readonly Similarity.SimWeight stats;
	internal readonly TermContext termStates;

	public TermWeight(TermQuery outerInstance, IndexSearcher searcher, TermContext termStates)
	{
	this.outerInstance = outerInstance;
	if (Debugging.AssertsEnabled) Debugging.Assert(termStates != null, "TermContext must not be null");
	this.termStates = termStates;
	this.similarity = searcher.Similarity;
	this.stats = similarity.ComputeWeight(outerInstance.Boost, searcher.CollectionStatistics(outerInstance.term.Field), searcher.TermStatistics(outerInstance.term, termStates));
	}

	public override string ToString()
	{
	return "weight(" + outerInstance + ")";
	}

	public override Query Query => outerInstance;

	public override float GetValueForNormalization()
	{
	return stats.GetValueForNormalization();
	}

	public override void Normalize(float queryNorm, float topLevelBoost)
	{
	stats.Normalize(queryNorm, topLevelBoost);
	}

	public override Scorer GetScorer(AtomicReaderContext context, IBits acceptDocs)
	{
	if (Debugging.AssertsEnabled) Debugging.Assert(termStates.TopReaderContext == ReaderUtil.GetTopLevelContext(context), () => "The top-reader used to create Weight (" + termStates.TopReaderContext + ") is not the same as the current reader's top-reader (" + ReaderUtil.GetTopLevelContext(context));
	TermsEnum termsEnum = GetTermsEnum(context);
	if (termsEnum == null)
	{
	return null;
	}
	DocsEnum docs = termsEnum.Docs(acceptDocs, null);
	if (Debugging.AssertsEnabled) Debugging.Assert(docs != null);
	return new TermScorer(this, docs, similarity.GetSimScorer(stats, context));
	}

	/// <summary>
	/// Returns a <see cref="TermsEnum"/> positioned at this weights <see cref="Index.Term"/> or <c>null</c> if
	/// the term does not exist in the given context.
	/// </summary>
	private TermsEnum GetTermsEnum(AtomicReaderContext context)
	{
	TermState state = termStates.Get(context.Ord);
	if (state == null) // term is not present in that reader
	{
	if (Debugging.AssertsEnabled) Debugging.Assert(TermNotInReader(context.AtomicReader, outerInstance.term), () => "no termstate found but term exists in reader term=" + outerInstance.term);
	return null;
	}
	//System.out.println("LD=" + reader.getLiveDocs() + " set?=" + (reader.getLiveDocs() != null ? reader.getLiveDocs().get(0) : "null"));
	TermsEnum termsEnum = context.AtomicReader.GetTerms(outerInstance.term.Field).GetEnumerator();
	termsEnum.SeekExact(outerInstance.term.Bytes, state);
	return termsEnum;
	}

	private bool TermNotInReader(AtomicReader reader, Term term)
	{
	// only called from assert
	//System.out.println("TQ.termNotInReader reader=" + reader + " term=" + field + ":" + bytes.utf8ToString());
	return reader.DocFreq(term) == 0;
	}

	public override Explanation Explain(AtomicReaderContext context, int doc)
	{
	Scorer scorer = GetScorer(context, context.AtomicReader.LiveDocs);
	if (scorer != null)
	{
	int newDoc = scorer.Advance(doc);
	if (newDoc == doc)
	{
	float freq = scorer.Freq;
	SimScorer docScorer = similarity.GetSimScorer(stats, context);
	ComplexExplanation result = new ComplexExplanation();
	result.Description = "weight(" + Query + " in " + doc + ") [" + similarity.GetType().Name + "], result of:";
	Explanation scoreExplanation = docScorer.Explain(doc, new Explanation(freq, "termFreq=" + freq));
	result.AddDetail(scoreExplanation);
	result.Value = scoreExplanation.Value;
	result.Match = true;
	return result;
	}
	}
	return new ComplexExplanation(false, 0.0f, "no matching term");
	}
	}

	/// <summary>
	/// Constructs a query for the term <paramref name="t"/>. </summary>
	public TermQuery(Term t)
	: this(t, -1)
	{
	}

	/// <summary>
	/// Expert: constructs a <see cref="TermQuery"/> that will use the
	/// provided <paramref name="docFreq"/> instead of looking up the docFreq
	/// against the searcher.
	/// </summary>
	public TermQuery(Term t, int docFreq)
	{
	term = t;
	this.docFreq = docFreq;
	perReaderTermState = null;
	}

	/// <summary>
	/// Expert: constructs a <see cref="TermQuery"/> that will use the
	/// provided docFreq instead of looking up the docFreq
	/// against the searcher.
	/// </summary>
	public TermQuery(Term t, TermContext states)
	{
	if (Debugging.AssertsEnabled) Debugging.Assert(states != null);
	term = t;
	docFreq = states.DocFreq;
	perReaderTermState = states;
	}

	/// <summary>
	/// Returns the term of this query. </summary>
	public virtual Term Term => term;

	public override Weight CreateWeight(IndexSearcher searcher)
	{
	IndexReaderContext context = searcher.TopReaderContext;
	TermContext termState;
	if (perReaderTermState == null \|\| perReaderTermState.TopReaderContext != context)
	{
	// make TermQuery single-pass if we don't have a PRTS or if the context differs!
	termState = TermContext.Build(context, term);
	}
	else
	{
	// PRTS was pre-build for this IS
	termState = this.perReaderTermState;
	}

	// we must not ignore the given docFreq - if set use the given value (lie)
	if (docFreq != -1)
	{
	termState.DocFreq = docFreq;
	}

	return new TermWeight(this, searcher, termState);
	}

	public override void ExtractTerms(ISet<Term> terms)
	{
	terms.Add(Term);
	}

	/// <summary>
	/// Prints a user-readable version of this query. </summary>
	public override string ToString(string field)
	{
	StringBuilder buffer = new StringBuilder();
	if (!term.Field.Equals(field, StringComparison.Ordinal))
	{
	buffer.Append(term.Field);
	buffer.Append(":");
	}
	buffer.Append(term.Text());
	buffer.Append(ToStringUtils.Boost(Boost));
	return buffer.ToString();
	}

	/// <summary>
	/// Returns <c>true</c> if <paramref name="o"/> is equal to this. </summary>
	public override bool Equals(object o)
	{
	if (!(o is TermQuery))
	{
	return false;
	}
	TermQuery other = (TermQuery)o;
	return (this.Boost == other.Boost) && this.term.Equals(other.term);
	}

	/// <summary>
	/// Returns a hash code value for this object. </summary>
	public override int GetHashCode()
	{
	return J2N.BitConversion.SingleToInt32Bits(Boost) ^ term.GetHashCode();
	}
	}
	}