| /* |
| * 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 System; |
| using System.Collections.Generic; |
| using Lucene.Net.Support; |
| |
| namespace Lucene.Net.Index |
| { |
| |
| /// <summary> For each Field, store position by position information. It ignores frequency information |
| /// <p/> |
| /// This is not thread-safe. |
| /// </summary> |
| public class PositionBasedTermVectorMapper:TermVectorMapper |
| { |
| private IDictionary<string, IDictionary<int, TVPositionInfo>> fieldToTerms; |
| |
| private System.String currentField; |
| /// <summary> A Map of Integer and TVPositionInfo</summary> |
| private IDictionary<int, TVPositionInfo> currentPositions; |
| private bool storeOffsets; |
| |
| public PositionBasedTermVectorMapper():base(false, false) |
| { |
| } |
| |
| public PositionBasedTermVectorMapper(bool ignoringOffsets):base(false, ignoringOffsets) |
| { |
| } |
| |
| /// <summary> Never ignores positions. This mapper doesn't make much sense unless there are positions</summary> |
| /// <value> false </value> |
| public override bool IsIgnoringPositions |
| { |
| get { return false; } |
| } |
| |
| /// <summary> Callback for the TermVectorReader. </summary> |
| /// <param name="term"> |
| /// </param> |
| /// <param name="frequency"> |
| /// </param> |
| /// <param name="offsets"> |
| /// </param> |
| /// <param name="positions"> |
| /// </param> |
| public override void Map(System.String term, int frequency, TermVectorOffsetInfo[] offsets, int[] positions) |
| { |
| for (int i = 0; i < positions.Length; i++) |
| { |
| System.Int32 posVal = positions[i]; |
| TVPositionInfo pos = currentPositions[posVal]; |
| if (pos == null) |
| { |
| pos = new TVPositionInfo(positions[i], storeOffsets); |
| currentPositions[posVal] = pos; |
| } |
| pos.addTerm(term, offsets != null ? offsets[i] : TermVectorOffsetInfo.Null); |
| } |
| } |
| |
| /// <summary> Callback mechanism used by the TermVectorReader</summary> |
| /// <param name="field"> The field being read |
| /// </param> |
| /// <param name="numTerms">The number of terms in the vector |
| /// </param> |
| /// <param name="storeOffsets">Whether offsets are available |
| /// </param> |
| /// <param name="storePositions">Whether positions are available |
| /// </param> |
| public override void SetExpectations(System.String field, int numTerms, bool storeOffsets, bool storePositions) |
| { |
| if (storePositions == false) |
| { |
| throw new System.SystemException("You must store positions in order to use this Mapper"); |
| } |
| if (storeOffsets == true) |
| { |
| //ignoring offsets |
| } |
| fieldToTerms = new HashMap<string, IDictionary<int, TVPositionInfo>>(numTerms); |
| this.storeOffsets = storeOffsets; |
| currentField = field; |
| currentPositions = new HashMap<int, TVPositionInfo>(); |
| fieldToTerms[currentField] = currentPositions; |
| } |
| |
| /// <summary> Get the mapping between fields and terms, sorted by the comparator |
| /// |
| /// </summary> |
| /// <value> A map between field names and a Map. The sub-Map key is the position as the integer, the value is <see cref="Lucene.Net.Index.PositionBasedTermVectorMapper.TVPositionInfo" />. </value> |
| public virtual IDictionary<string, IDictionary<int, TVPositionInfo>> FieldToTerms |
| { |
| get { return fieldToTerms; } |
| } |
| |
| /// <summary> Container for a term at a position</summary> |
| public class TVPositionInfo |
| { |
| /// <summary> </summary> |
| /// <returns> The position of the term |
| /// </returns> |
| virtual public int Position |
| { |
| get |
| { |
| return position; |
| } |
| |
| } |
| /// <summary> Note, there may be multiple terms at the same position</summary> |
| /// <returns> A List of Strings |
| /// </returns> |
| virtual public IList<String> Terms |
| { |
| get |
| { |
| return terms; |
| } |
| |
| } |
| /// <summary> Parallel list (to <see cref="Terms" />) of TermVectorOffsetInfo objects. |
| /// There may be multiple entries since there may be multiple terms at a position</summary> |
| /// <returns> A List of TermVectorOffsetInfo objects, if offsets are store. |
| /// </returns> |
| virtual public IList<TermVectorOffsetInfo> Offsets |
| { |
| get |
| { |
| return offsets; |
| } |
| |
| } |
| private int position; |
| //a list of Strings |
| private IList<string> terms; |
| //A list of TermVectorOffsetInfo |
| private IList<TermVectorOffsetInfo> offsets; |
| |
| |
| public TVPositionInfo(int position, bool storeOffsets) |
| { |
| this.position = position; |
| terms = new List<string>(); |
| if (storeOffsets) |
| { |
| offsets = new List<TermVectorOffsetInfo>(); |
| } |
| } |
| |
| internal virtual void addTerm(System.String term, TermVectorOffsetInfo info) |
| { |
| terms.Add(term); |
| if (offsets != null) |
| { |
| offsets.Add(info); |
| } |
| } |
| } |
| } |
| } |