| using System; |
| using Lucene.Net.Analysis; |
| using Lucene.Net.Analysis.TokenAttributes; |
| |
| namespace Lucene.Net.Search.Highlight |
| { |
| /* |
| * 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> |
| /// One, or several overlapping tokens, along with the score(s) and the scope of |
| /// the original text |
| /// </summary> |
| public class TokenGroup |
| { |
| private const int MAX_NUM_TOKENS_PER_GROUP = 50; |
| |
| internal Token[] tokens = new Token[MAX_NUM_TOKENS_PER_GROUP]; |
| internal float[] scores = new float[MAX_NUM_TOKENS_PER_GROUP]; |
| |
| internal int MatchStartOffset { get; set; } |
| internal int MatchEndOffset { get; set; } |
| |
| /// <summary> |
| /// the number of tokens in this group |
| /// </summary> |
| public virtual int NumTokens { get; internal set; } = 0; |
| |
| /// <summary> |
| /// the start position in the original text |
| /// </summary> |
| public virtual int StartOffset { get; internal set; } = 0; |
| |
| /// <summary> |
| /// the end position in the original text |
| /// </summary> |
| public virtual int EndOffset { get; private set; } = 0; |
| |
| /// <summary> |
| /// all tokens' scores summed up |
| /// </summary> |
| public virtual float TotalScore { get; private set; } |
| |
| private readonly IOffsetAttribute offsetAtt; // LUCENENET: marked readonly |
| private readonly ICharTermAttribute termAtt; // LUCENENET: marked readonly |
| |
| public TokenGroup(TokenStream tokenStream) |
| { |
| offsetAtt = tokenStream.AddAttribute<IOffsetAttribute>(); |
| termAtt = tokenStream.AddAttribute<ICharTermAttribute>(); |
| } |
| |
| internal void AddToken(float score) |
| { |
| if (NumTokens < MAX_NUM_TOKENS_PER_GROUP) |
| { |
| int termStartOffset = offsetAtt.StartOffset; |
| int termEndOffset = offsetAtt.EndOffset; |
| if (NumTokens == 0) |
| { |
| StartOffset = MatchStartOffset = termStartOffset; |
| EndOffset = MatchEndOffset = termEndOffset; |
| TotalScore += score; |
| } |
| else |
| { |
| StartOffset = Math.Min(StartOffset, termStartOffset); |
| EndOffset = Math.Max(EndOffset, termEndOffset); |
| if (score > 0) |
| { |
| if (TotalScore == 0) |
| { |
| MatchStartOffset = termStartOffset; |
| MatchEndOffset = termEndOffset; |
| } |
| else |
| { |
| MatchStartOffset = Math.Min(MatchStartOffset, termStartOffset); |
| MatchEndOffset = Math.Max(MatchEndOffset, termEndOffset); |
| } |
| TotalScore += score; |
| } |
| } |
| Token token = new Token(termStartOffset, termEndOffset); |
| token.SetEmpty().Append(termAtt); |
| tokens[NumTokens] = token; |
| scores[NumTokens] = score; |
| NumTokens++; |
| } |
| } |
| |
| internal bool IsDistinct() |
| { |
| return offsetAtt.StartOffset >= EndOffset; |
| } |
| |
| internal void Clear() |
| { |
| NumTokens = 0; |
| TotalScore = 0; |
| } |
| |
| /// <summary> |
| /// the "n"th token |
| /// </summary> |
| /// <param name="index">a value between 0 and numTokens -1</param> |
| public virtual Token GetToken(int index) |
| { |
| return tokens[index]; |
| } |
| |
| /// <summary> |
| /// the "n"th score |
| /// </summary> |
| /// <param name="index">a value between 0 and numTokens -1</param> |
| public virtual float GetScore(int index) |
| { |
| return scores[index]; |
| } |
| } |
| } |