| using Lucene.Net.Diagnostics; |
| using System.Text; |
| |
| 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. |
| */ |
| |
| using IBits = Lucene.Net.Util.IBits; |
| |
| /// <summary> |
| /// Concatenates multiple <see cref="IBits"/> together, on every lookup. |
| /// |
| /// <para/><b>NOTE</b>: this is very costly, as every lookup must |
| /// do a binary search to locate the right sub-reader. |
| /// <para/> |
| /// @lucene.experimental |
| /// </summary> |
| internal sealed class MultiBits : IBits |
| { |
| private readonly IBits[] subs; |
| |
| // length is 1+subs.length (the last entry has the maxDoc): |
| private readonly int[] starts; |
| |
| private readonly bool sefaultValue; |
| |
| public MultiBits(IBits[] subs, int[] starts, bool defaultValue) |
| { |
| if (Debugging.AssertsEnabled) Debugging.Assert(starts.Length == 1 + subs.Length); |
| this.subs = subs; |
| this.starts = starts; |
| this.sefaultValue = defaultValue; |
| } |
| |
| private bool CheckLength(int reader, int doc) |
| { |
| int length = starts[1 + reader] - starts[reader]; |
| if (Debugging.AssertsEnabled) Debugging.Assert(doc - starts[reader] < length, () => "doc=" + doc + " reader=" + reader + " starts[reader]=" + starts[reader] + " length=" + length); |
| return true; |
| } |
| |
| public bool Get(int doc) |
| { |
| int reader = ReaderUtil.SubIndex(doc, starts); |
| if (Debugging.AssertsEnabled) Debugging.Assert(reader != -1); |
| IBits bits = subs[reader]; |
| if (bits == null) |
| { |
| return sefaultValue; |
| } |
| else |
| { |
| if (Debugging.AssertsEnabled) Debugging.Assert(CheckLength(reader, doc)); |
| return bits.Get(doc - starts[reader]); |
| } |
| } |
| |
| public override string ToString() |
| { |
| StringBuilder b = new StringBuilder(); |
| b.Append(subs.Length + " subs: "); |
| for (int i = 0; i < subs.Length; i++) |
| { |
| if (i != 0) |
| { |
| b.Append("; "); |
| } |
| if (subs[i] == null) |
| { |
| b.Append("s=" + starts[i] + " l=null"); |
| } |
| else |
| { |
| b.Append("s=" + starts[i] + " l=" + subs[i].Length + " b=" + subs[i]); |
| } |
| } |
| b.Append(" end=" + starts[subs.Length]); |
| return b.ToString(); |
| } |
| |
| /// <summary> |
| /// Represents a sub-Bits from |
| /// <see cref="MultiBits.GetMatchingSub(Lucene.Net.Index.ReaderSlice)"/>. |
| /// </summary> |
| public sealed class SubResult |
| { |
| public bool Matches { get; internal set; } |
| public IBits Result { get; internal set; } |
| } |
| |
| /// <summary> |
| /// Returns a sub-Bits matching the provided <paramref name="slice"/> |
| /// <para/> |
| /// Because <c>null</c> usually has a special meaning for |
| /// <see cref="IBits"/> (e.g. no deleted documents), you must check |
| /// <see cref="SubResult.Matches"/> instead to ensure the sub was |
| /// actually found. |
| /// </summary> |
| public SubResult GetMatchingSub(ReaderSlice slice) |
| { |
| int reader = ReaderUtil.SubIndex(slice.Start, starts); |
| if (Debugging.AssertsEnabled) |
| { |
| Debugging.Assert(reader != -1); |
| Debugging.Assert(reader < subs.Length, () => "slice=" + slice + " starts[-1]=" + starts[starts.Length - 1]); |
| } |
| SubResult subResult = new SubResult(); |
| if (starts[reader] == slice.Start && starts[1 + reader] == slice.Start + slice.Length) |
| { |
| subResult.Matches = true; |
| subResult.Result = subs[reader]; |
| } |
| else |
| { |
| subResult.Matches = false; |
| } |
| return subResult; |
| } |
| |
| public int Length => starts[starts.Length - 1]; |
| } |
| } |