| /* |
| * 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 Lucene.Net.Support; |
| using IndexInput = Lucene.Net.Store.IndexInput; |
| |
| namespace Lucene.Net.Index |
| { |
| |
| /// <summary> Implements the skip list reader for the default posting list format |
| /// that stores positions and payloads. |
| /// |
| /// </summary> |
| class DefaultSkipListReader:MultiLevelSkipListReader |
| { |
| private bool currentFieldStoresPayloads; |
| private readonly long[] freqPointer; |
| private readonly long[] proxPointer; |
| private readonly int[] payloadLength; |
| |
| private long lastFreqPointer; |
| private long lastProxPointer; |
| private int lastPayloadLength; |
| |
| |
| internal DefaultSkipListReader(IndexInput skipStream, int maxSkipLevels, int skipInterval):base(skipStream, maxSkipLevels, skipInterval) |
| { |
| freqPointer = new long[maxSkipLevels]; |
| proxPointer = new long[maxSkipLevels]; |
| payloadLength = new int[maxSkipLevels]; |
| } |
| |
| internal virtual void Init(long skipPointer, long freqBasePointer, long proxBasePointer, int df, bool storesPayloads) |
| { |
| base.Init(skipPointer, df); |
| this.currentFieldStoresPayloads = storesPayloads; |
| lastFreqPointer = freqBasePointer; |
| lastProxPointer = proxBasePointer; |
| |
| for (int i = 0; i < freqPointer.Length; i++) freqPointer[i] = freqBasePointer; |
| for (int i = 0; i < proxPointer.Length; i++) proxPointer[i] = proxBasePointer; |
| for (int i = 0; i < payloadLength.Length; i++) payloadLength[i] = 0; |
| } |
| |
| /// <summary>Returns the freq pointer of the doc to which the last call of |
| /// <see cref="MultiLevelSkipListReader.SkipTo(int)" /> has skipped. |
| /// </summary> |
| internal virtual long GetFreqPointer() |
| { |
| return lastFreqPointer; |
| } |
| |
| /// <summary>Returns the prox pointer of the doc to which the last call of |
| /// <see cref="MultiLevelSkipListReader.SkipTo(int)" /> has skipped. |
| /// </summary> |
| internal virtual long GetProxPointer() |
| { |
| return lastProxPointer; |
| } |
| |
| /// <summary>Returns the payload length of the payload stored just before |
| /// the doc to which the last call of <see cref="MultiLevelSkipListReader.SkipTo(int)" /> |
| /// has skipped. |
| /// </summary> |
| internal virtual int GetPayloadLength() |
| { |
| return lastPayloadLength; |
| } |
| |
| protected internal override void SeekChild(int level) |
| { |
| base.SeekChild(level); |
| freqPointer[level] = lastFreqPointer; |
| proxPointer[level] = lastProxPointer; |
| payloadLength[level] = lastPayloadLength; |
| } |
| |
| protected internal override void SetLastSkipData(int level) |
| { |
| base.SetLastSkipData(level); |
| lastFreqPointer = freqPointer[level]; |
| lastProxPointer = proxPointer[level]; |
| lastPayloadLength = payloadLength[level]; |
| } |
| |
| |
| protected internal override int ReadSkipData(int level, IndexInput skipStream) |
| { |
| int delta; |
| if (currentFieldStoresPayloads) |
| { |
| // the current field stores payloads. |
| // if the doc delta is odd then we have |
| // to read the current payload length |
| // because it differs from the length of the |
| // previous payload |
| delta = skipStream.ReadVInt(); |
| if ((delta & 1) != 0) |
| { |
| payloadLength[level] = skipStream.ReadVInt(); |
| } |
| delta = Number.URShift(delta, 1); |
| } |
| else |
| { |
| delta = skipStream.ReadVInt(); |
| } |
| freqPointer[level] += skipStream.ReadVInt(); |
| proxPointer[level] += skipStream.ReadVInt(); |
| |
| return delta; |
| } |
| } |
| } |