1   /**
2    * Distribution License:
3    * JSword is free software; you can redistribute it and/or modify it under
4    * the terms of the GNU Lesser General Public License, version 2.1 as published by
5    * the Free Software Foundation. This program is distributed in the hope
6    * that it will be useful, but WITHOUT ANY WARRANTY; without even the
7    * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
8    * See the GNU Lesser General Public License for more details.
9    *
10   * The License is available on the internet at:
11   *       http://www.gnu.org/copyleft/lgpl.html
12   * or by writing to:
13   *      Free Software Foundation, Inc.
14   *      59 Temple Place - Suite 330
15   *      Boston, MA 02111-1307, USA
16   *
17   * Copyright: 2007
18   *     The copyright to this program is held by it's authors.
19   *
20   * ID: $Id: XRefAnalyzer.java 2050 2010-12-09 15:31:45Z dmsmith $
21   */
22  package org.crosswire.jsword.index.lucene.analysis;
23  
24  import java.io.IOException;
25  import java.io.Reader;
26  
27  import org.apache.lucene.analysis.TokenStream;
28  import org.apache.lucene.analysis.WhitespaceTokenizer;
29  import org.crosswire.jsword.book.Book;
30  
31  /**
32   * A specialized analyzer that normalizes Cross References.
33   * 
34   * @see gnu.lgpl.License for license details.<br>
35   *      The copyright to this program is held by it's authors.
36   * @author DM Smith [dmsmith555 at yahoo dot com]
37   */
38  public class XRefAnalyzer extends AbstractBookAnalyzer {
39      /**
40       * Construct a default XRefAnalyzer.
41       */
42      public XRefAnalyzer() {
43      }
44  
45      /**
46       * Construct an XRefAnalyzer tied to a book.
47       */
48      public XRefAnalyzer(Book book) {
49          setBook(book);
50      }
51  
52      /*
53       * (non-Javadoc)
54       * 
55       * @see org.apache.lucene.analysis.Analyzer#tokenStream(java.lang.String,
56       * java.io.Reader)
57       */
58      @Override
59      public TokenStream tokenStream(String fieldName, Reader reader) {
60          return new KeyFilter(getBook(), new WhitespaceTokenizer(reader));
61      }
62  
63      /* (non-Javadoc)
64       * @see org.apache.lucene.analysis.Analyzer#reusableTokenStream(java.lang.String, java.io.Reader)
65       */
66      @Override
67      public TokenStream reusableTokenStream(String fieldName, Reader reader) throws IOException {
68          SavedStreams streams = (SavedStreams) getPreviousTokenStream();
69          if (streams == null) {
70              streams = new SavedStreams(new WhitespaceTokenizer(reader));
71              streams.setResult(new KeyFilter(getBook(), streams.getResult()));
72              setPreviousTokenStream(streams);
73          } else {
74              streams.getSource().reset(reader);
75          }
76          return streams.getResult();
77      }
78  }
79