| using Lucene.Net.Diagnostics; |
| using Lucene.Net.Support; |
| using System.Diagnostics.CodeAnalysis; |
| |
| namespace Lucene.Net.Index |
| { |
| /* |
| * 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> |
| /// Exposes <see cref="DocsEnum"/>, merged from <see cref="DocsEnum"/> |
| /// API of sub-segments. |
| /// <para/> |
| /// @lucene.experimental |
| /// </summary> |
| |
| public sealed class MultiDocsEnum : DocsEnum |
| { |
| private readonly MultiTermsEnum parent; |
| internal readonly DocsEnum[] subDocsEnum; |
| private EnumWithSlice[] subs; |
| internal int numSubs; |
| internal int upto; |
| internal DocsEnum current; |
| internal int currentBase; |
| internal int doc = -1; |
| |
| /// <summary> |
| /// Sole constructor </summary> |
| /// <param name="parent"> The <see cref="MultiTermsEnum"/> that created us. </param> |
| /// <param name="subReaderCount"> How many sub-readers are being merged. </param> |
| public MultiDocsEnum(MultiTermsEnum parent, int subReaderCount) |
| { |
| this.parent = parent; |
| subDocsEnum = new DocsEnum[subReaderCount]; |
| } |
| |
| internal MultiDocsEnum Reset(EnumWithSlice[] subs, int numSubs) |
| { |
| this.numSubs = numSubs; |
| |
| this.subs = new EnumWithSlice[subs.Length]; |
| for (int i = 0; i < subs.Length; i++) |
| { |
| this.subs[i] = new EnumWithSlice(); |
| this.subs[i].DocsEnum = subs[i].DocsEnum; |
| this.subs[i].Slice = subs[i].Slice; |
| } |
| upto = -1; |
| doc = -1; |
| current = null; |
| return this; |
| } |
| |
| /// <summary> |
| /// Returns <c>true</c> if this instance can be reused by |
| /// the provided <see cref="MultiTermsEnum"/>. |
| /// </summary> |
| public bool CanReuse(MultiTermsEnum parent) |
| { |
| return this.parent == parent; |
| } |
| |
| /// <summary> |
| /// How many sub-readers we are merging. </summary> |
| /// <seealso cref="Subs"/> |
| public int NumSubs => numSubs; |
| |
| /// <summary> |
| /// Returns sub-readers we are merging. </summary> |
| [WritableArray] |
| [SuppressMessage("Microsoft.Performance", "CA1819", Justification = "Lucene's design requires some writable array properties")] |
| public EnumWithSlice[] Subs => subs; |
| |
| public override int Freq => current.Freq; |
| |
| public override int DocID => doc; |
| |
| public override int Advance(int target) |
| { |
| if (Debugging.AssertsEnabled) Debugging.Assert(target > doc); |
| while (true) |
| { |
| if (current != null) |
| { |
| int doc; |
| if (target < currentBase) |
| { |
| // target was in the previous slice but there was no matching doc after it |
| doc = current.NextDoc(); |
| } |
| else |
| { |
| doc = current.Advance(target - currentBase); |
| } |
| if (doc == NO_MORE_DOCS) |
| { |
| current = null; |
| } |
| else |
| { |
| return this.doc = doc + currentBase; |
| } |
| } |
| else if (upto == numSubs - 1) |
| { |
| return this.doc = NO_MORE_DOCS; |
| } |
| else |
| { |
| upto++; |
| current = subs[upto].DocsEnum; |
| currentBase = subs[upto].Slice.Start; |
| } |
| } |
| } |
| |
| public override int NextDoc() |
| { |
| while (true) |
| { |
| if (current == null) |
| { |
| if (upto == numSubs - 1) |
| { |
| return this.doc = NO_MORE_DOCS; |
| } |
| else |
| { |
| upto++; |
| current = subs[upto].DocsEnum; |
| currentBase = subs[upto].Slice.Start; |
| } |
| } |
| |
| int doc = current.NextDoc(); |
| if (doc != NO_MORE_DOCS) |
| { |
| return this.doc = currentBase + doc; |
| } |
| else |
| { |
| current = null; |
| } |
| } |
| } |
| |
| public override long GetCost() |
| { |
| long cost = 0; |
| for (int i = 0; i < numSubs; i++) |
| { |
| cost += subs[i].DocsEnum.GetCost(); |
| } |
| return cost; |
| } |
| |
| // TODO: implement bulk read more efficiently than super |
| /// <summary> |
| /// Holds a <see cref="Index.DocsEnum"/> along with the |
| /// corresponding <see cref="ReaderSlice"/>. |
| /// </summary> |
| public sealed class EnumWithSlice |
| { |
| internal EnumWithSlice() |
| { |
| } |
| |
| /// <summary> |
| /// <see cref="Index.DocsEnum"/> of this sub-reader. </summary> |
| public DocsEnum DocsEnum { get; internal set; } // LUCENENET NOTE: Made setter internal because ctor is internal |
| |
| /// <summary> |
| /// <see cref="ReaderSlice"/> describing how this sub-reader |
| /// fits into the composite reader. |
| /// </summary> |
| public ReaderSlice Slice { get; internal set; } // LUCENENET NOTE: Made setter internal because ctor is internal |
| |
| public override string ToString() |
| { |
| return Slice.ToString() + ":" + DocsEnum; |
| } |
| } |
| |
| public override string ToString() |
| { |
| return "MultiDocsEnum(" + Arrays.ToString(Subs) + ")"; |
| } |
| } |
| } |