Lucene.Net  3.0.3
Lucene.Net is a port of the Lucene search engine library, written in C# and targeted at .NET runtime users.
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ChineseAnalyzer.cs
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21 
22 using System;
23 using System.IO;
24 using System.Text;
25 using System.Collections;
26 
27 using Lucene.Net.Analysis;
28 
29 namespace Lucene.Net.Analysis.Cn
30 {
31  /// <summary>
32  /// An <see cref="Analyzer"/> that tokenizes text with <see cref="ChineseTokenizer"/> and
33  /// filters with <see cref="ChineseFilter"/>
34  /// </summary>
35  public class ChineseAnalyzer : Analyzer
36  {
37 
38  public ChineseAnalyzer()
39  {
40  }
41 
42  /// <summary>
43  /// Creates a TokenStream which tokenizes all the text in the provided Reader.
44  /// </summary>
45  /// <returns>A TokenStream build from a ChineseTokenizer filtered with ChineseFilter.</returns>
46  public override sealed TokenStream TokenStream(String fieldName, TextReader reader)
47  {
48  TokenStream result = new ChineseTokenizer(reader);
49  result = new ChineseFilter(result);
50  return result;
51  }
52 
53  private class SavedStreams
54  {
55  protected internal Tokenizer source;
56  protected internal TokenStream result;
57  };
58 
59  /// <summary>
60  /// Returns a (possibly reused) <see cref="TokenStream"/> which tokenizes all the text in the
61  /// provided <see cref="TextReader"/>.
62  /// </summary>
63  /// <returns>
64  /// A <see cref="TokenStream"/> built from a <see cref="ChineseTokenizer"/>
65  /// filtered with <see cref="ChineseFilter"/>.
66  /// </returns>
67  public override TokenStream ReusableTokenStream(String fieldName, TextReader reader)
68  {
69  /* tokenStream() is final, no back compat issue */
70  SavedStreams streams = (SavedStreams) PreviousTokenStream;
71  if (streams == null)
72  {
73  streams = new SavedStreams();
74  streams.source = new ChineseTokenizer(reader);
75  streams.result = new ChineseFilter(streams.source);
76  PreviousTokenStream = streams;
77  }
78  else
79  {
80  streams.source.Reset(reader);
81  }
82  return streams.result;
83  }
84  }
85 }