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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DateRecognizerSinkFilter.cs
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1 /*
2  *
3  * Licensed to the Apache Software Foundation (ASF) under one
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11  * http://www.apache.org/licenses/LICENSE-2.0
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21 
22 using System;
23 using System.Collections.Generic;
24 using System.Linq;
25 using System.Text;
26 using Lucene.Net.Analysis.Tokenattributes;
27 using Lucene.Net.Util;
28 
29 namespace Lucene.Net.Analysis.Sinks
30 {
31  /*
32  * Attempts to parse the {@link org.apache.lucene.analysis.Token#termBuffer()} as a Date using a <see cref="System.IFormatProvider"/>.
33  * If the value is a Date, it will add it to the sink.
34  * <p/>
35  *
36  **/
37  public class DateRecognizerSinkFilter : TeeSinkTokenFilter.SinkFilter
38  {
39  public const string DATE_TYPE = "date";
40 
41  protected IFormatProvider dateFormat;
43 
44  /*
45  * Uses <see cref="System.Globalization.CultureInfo.CurrentCulture.DateTimeFormatInfo"/> as the <see cref="IFormatProvider"/> object.
46  */
48  : this(System.Globalization.CultureInfo.CurrentCulture)
49  {
50 
51  }
52 
53  public DateRecognizerSinkFilter(IFormatProvider dateFormat)
54  {
55  this.dateFormat = dateFormat;
56  }
57 
58  public override bool Accept(AttributeSource source)
59  {
60  if (termAtt == null)
61  {
62  termAtt = source.AddAttribute<ITermAttribute>();
63  }
64  try
65  {
66  DateTime date = DateTime.Parse(termAtt.Term, dateFormat);//We don't care about the date, just that we can parse it as a date
67  if (date != null)
68  {
69  return true;
70  }
71  }
72  catch (FormatException)
73  {
74 
75  }
76 
77  return false;
78  }
79 
80  }
81 }