Lucene.Net/Analysis/TokenStream.cs

   1 namespace Lucene.Net.Analysis
   2 {
   3         /* ====================================================================
   4          * The Apache Software License, Version 1.1
   5          *
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  10          * modification, are permitted provided that the following conditions
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  12          *
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  56
  57         /// <summary>
  58         /// A TokenStream enumerates the sequence of tokens, either from
  59         ///     fields of a document or from query text.
  60         ///     <p>This is an abstract class.  Concrete subclasses are:</p>
  61         ///     <ul>
  62         ///   <li>Tokenizer, a TokenStream whose input is a Reader; and </li>
  63         ///       <li>TokenFilter, a TokenStream whose input is another TokenStream.</li>
  64         ///     </ul>
  65         /// </summary>
  66         public abstract class TokenStream
  67         {
  68                 /// <summary>
  69                 /// Returns the next token in the stream, or null at EOS.
  70                 /// </summary>
  71                 /// <returns></returns>
  72                 public abstract Token Next();
  73
  74                 /// <summary>
  75                 /// Releases resources associated with this stream.
  76                 /// </summary>
  77                 public virtual void Close() {}
  78         }
  79 }