| using Lucene.Net.Index; |
| using Lucene.Net.Util; |
| using System.Collections.Generic; |
| using System.IO; |
| |
| namespace Lucene.Net.Search.Grouping |
| { |
| /* |
| * 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> |
| /// This collector specializes in collecting the most relevant document (group head) for each group that match the query. |
| /// |
| /// @lucene.experimental |
| /// </summary> |
| /// <typeparam name="GH"></typeparam> |
| public abstract class AbstractAllGroupHeadsCollector<GH> : AbstractAllGroupHeadsCollector |
| where GH : AbstractAllGroupHeadsCollector_GroupHead |
| { |
| protected readonly int[] m_reversed; |
| protected readonly int m_compIDXEnd; |
| protected readonly TemporalResult m_temporalResult; |
| |
| protected AbstractAllGroupHeadsCollector(int numberOfSorts) |
| { |
| this.m_reversed = new int[numberOfSorts]; |
| this.m_compIDXEnd = numberOfSorts - 1; |
| m_temporalResult = new TemporalResult(); |
| } |
| |
| /// <summary> |
| /// |
| /// </summary> |
| /// <param name="maxDoc">The maxDoc of the top level <see cref="Index.IndexReader"/></param> |
| /// <returns>a <see cref="FixedBitSet"/> containing all group heads.</returns> |
| public override FixedBitSet RetrieveGroupHeads(int maxDoc) |
| { |
| FixedBitSet bitSet = new FixedBitSet(maxDoc); |
| |
| ICollection<GH> groupHeads = CollectedGroupHeads; |
| foreach (GH groupHead in groupHeads) |
| { |
| bitSet.Set(groupHead.Doc); |
| } |
| |
| return bitSet; |
| } |
| |
| /// <summary> |
| /// |
| /// </summary> |
| /// <returns>an int array containing all group heads. The size of the array is equal to number of collected unique groups.</returns> |
| public override int[] RetrieveGroupHeads() |
| { |
| ICollection<GH> groupHeads = CollectedGroupHeads; |
| int[] docHeads = new int[groupHeads.Count]; |
| |
| int i = 0; |
| foreach (GH groupHead in groupHeads) |
| { |
| docHeads[i++] = groupHead.Doc; |
| } |
| |
| return docHeads; |
| } |
| |
| /// <summary> |
| /// The number of group heads found for a query. |
| /// LUCENENET NOTE: This was groupHeadsSize() in Lucene |
| /// </summary> |
| /// <returns>the number of group heads found for a query.</returns> |
| public override int GroupHeadsCount => CollectedGroupHeads.Count; |
| |
| /// <summary> |
| /// Returns the group head and puts it into <see cref="TemporalResult"/>. |
| /// If the group head wasn't encountered before then it will be added to the collected group heads. |
| /// <para> |
| /// The <see cref="TemporalResult.Stop"/> property will be <c>true</c> if the group head wasn't encountered before |
| /// otherwise <c>false</c>. |
| /// </para> |
| /// </summary> |
| /// <param name="doc">The document to retrieve the group head for.</param> |
| /// <exception cref="IOException">If I/O related errors occur</exception> |
| protected override abstract void RetrieveGroupHeadAndAddIfNotExist(int doc); |
| |
| /// <summary> |
| /// Returns the collected group heads. |
| /// Subsequent calls should return the same group heads. |
| /// </summary> |
| /// <returns>the collected group heads</returns> |
| protected abstract ICollection<GH> CollectedGroupHeads { get; } |
| |
| public override void Collect(int doc) |
| { |
| RetrieveGroupHeadAndAddIfNotExist(doc); |
| if (m_temporalResult.Stop) |
| { |
| return; |
| } |
| GH groupHead = m_temporalResult.GroupHead; |
| |
| // Ok now we need to check if the current doc is more relevant then current doc for this group |
| for (int compIDX = 0; ; compIDX++) |
| { |
| int c = m_reversed[compIDX] * groupHead.Compare(compIDX, doc); |
| if (c < 0) |
| { |
| // Definitely not competitive. So don't even bother to continue |
| return; |
| } |
| else if (c > 0) |
| { |
| // Definitely competitive. |
| break; |
| } |
| else if (compIDX == m_compIDXEnd) |
| { |
| // Here c=0. If we're at the last comparer, this doc is not |
| // competitive, since docs are visited in doc Id order, which means |
| // this doc cannot compete with any other document in the queue. |
| return; |
| } |
| } |
| groupHead.UpdateDocHead(doc); |
| } |
| |
| public override bool AcceptsDocsOutOfOrder => false; |
| |
| /// <summary> |
| /// Contains the result of group head retrieval. |
| /// To prevent new object creations of this class for every collect. |
| /// </summary> |
| protected class TemporalResult |
| { |
| public GH GroupHead { get; set; } |
| public bool Stop { get; set; } |
| } |
| } |
| |
| /// <summary> |
| /// Represents a group head. A group head is the most relevant document for a particular group. |
| /// The relevancy is based is usually based on the sort. |
| /// <para> |
| /// The group head contains a group value with its associated most relevant document id. |
| /// </para> |
| /// </summary> |
| /// <remarks> |
| /// LUCENENET: moved this class from being a nested class of <see cref="AbstractAllGroupHeadsCollector{TGroupValue}"/>, |
| /// made it non-generic so the generic closing type doesn't need to be specified in classes that |
| /// use <see cref="AbstractAllGroupHeadsCollector_GroupHead"/> as a generic closing type, and renamed |
| /// it from GroupHead to <see cref="AbstractAllGroupHeadsCollector_GroupHead"/> to avoid naming conflicts with nested classes |
| /// named GroupHead in derived classes of <see cref="AbstractAllGroupHeadsCollector"/>. |
| /// </remarks> |
| public abstract class AbstractAllGroupHeadsCollector_GroupHead /*<TGroupValue>*/ |
| { |
| |
| //public readonly TGroupValue groupValue; |
| public int Doc { get; protected set; } |
| |
| protected AbstractAllGroupHeadsCollector_GroupHead(/*TGroupValue groupValue,*/ int doc) |
| { |
| //this.groupValue = groupValue; |
| this.Doc = doc; |
| } |
| |
| /// <summary> |
| /// Compares the specified document for a specified comparer against the current most relevant document. |
| /// </summary> |
| /// <param name="compIDX">The comparer index of the specified comparer.</param> |
| /// <param name="doc">The specified document.</param> |
| /// <returns> |
| /// -1 if the specified document wasn't competitive against the current most relevant document, 1 if the |
| /// specified document was competitive against the current most relevant document. Otherwise 0. |
| /// </returns> |
| /// <exception cref="IOException">If I/O related errors occur</exception> |
| public abstract int Compare(int compIDX, int doc); |
| |
| /// <summary> |
| /// Updates the current most relevant document with the specified document. |
| /// </summary> |
| /// <param name="doc">The specified document</param> |
| /// <exception cref="IOException">If I/O related errors occur</exception> |
| public abstract void UpdateDocHead(int doc); |
| } |
| |
| /// <summary> |
| /// LUCENENET specific class used to reference an |
| /// <see cref="AbstractAllGroupHeadsCollector{GH}"/> subclass |
| /// without refering to its generic closing type. |
| /// </summary> |
| public abstract class AbstractAllGroupHeadsCollector : ICollector |
| { |
| /// <summary> |
| /// |
| /// </summary> |
| /// <param name="maxDoc">The maxDoc of the top level <see cref="Index.IndexReader"/></param> |
| /// <returns>a <see cref="FixedBitSet"/> containing all group heads.</returns> |
| public abstract FixedBitSet RetrieveGroupHeads(int maxDoc); |
| |
| /// <summary> |
| /// |
| /// </summary> |
| /// <returns>an int array containing all group heads. The size of the array is equal to number of collected unique groups.</returns> |
| public abstract int[] RetrieveGroupHeads(); |
| |
| /// <summary> |
| /// The number of group heads found for a query. |
| /// LUCENENET NOTE: This was groupHeadsSize() in Lucene |
| /// </summary> |
| /// <returns>the number of group heads found for a query.</returns> |
| public abstract int GroupHeadsCount { get; } |
| |
| /// <summary> |
| /// Returns the group head and puts it into <see cref="AbstractAllGroupHeadsCollector{GH}.TemporalResult"/>. |
| /// If the group head wasn't encountered before then it will be added to the collected group heads. |
| /// <para> |
| /// The <see cref="AbstractAllGroupHeadsCollector{GH}.TemporalResult.Stop"/> property will be <c>true</c> if the group head wasn't encountered before |
| /// otherwise <c>false</c>. |
| /// </para> |
| /// </summary> |
| /// <param name="doc">The document to retrieve the group head for.</param> |
| /// <exception cref="IOException">If I/O related errors occur</exception> |
| protected abstract void RetrieveGroupHeadAndAddIfNotExist(int doc); |
| |
| |
| // LUCENENET specific - we need to implement these here, since our abstract base class |
| // is now an interface. |
| /// <summary> |
| /// Called before successive calls to <see cref="Collect(int)"/>. Implementations |
| /// that need the score of the current document (passed-in to |
| /// <also cref="Collect(int)"/>), should save the passed-in <see cref="Scorer"/> and call |
| /// scorer.Score() when needed. |
| /// </summary> |
| public abstract void SetScorer(Scorer scorer); |
| |
| /// <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); |
| |
| /// <summary> |
| /// Return <c>true</c> if this collector does not |
| /// require the matching docIDs to be delivered in int sort |
| /// order (smallest to largest) to <see cref="Collect"/>. |
| /// |
| /// <para> Most Lucene Query implementations will visit |
| /// matching docIDs in order. However, some queries |
| /// (currently limited to certain cases of <see cref="BooleanQuery"/>) |
| /// can achieve faster searching if the |
| /// <see cref="ICollector"/> allows them to deliver the |
| /// docIDs out of order.</para> |
| /// |
| /// <para> Many collectors don't mind getting docIDs out of |
| /// order, so it's important to return <c>true</c> |
| /// here.</para> |
| /// </summary> |
| public abstract bool AcceptsDocsOutOfOrder { get; } |
| } |
| } |