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1   /*
2    * Copyright (c) 2007, Peter Mika All rights reserved.
3    * 
4    * Redistribution and use in source and binary forms, with or without
5    * modification, are permitted provided that the following conditions are met:
6    * 
7    * - Redistributions of source code must retain the above copyright notice, this
8    *   list of conditions and the following disclaimer.
9    * - Redistributions in binary form must reproduce the above copyright notice,
10   *   this list of conditions and the following disclaimer in the documentation
11   *   and/or other materials provided with the distribution. 
12   * - Neither the name of the openrdf.org nor the names of its contributors may
13   *   be used to endorse or promote products derived from this software without
14   *   specific prior written permission.
15   * 
16   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26   * POSSIBILITY OF SUCH DAMAGE.
27   * 
28   */
29  package org.openrdf.elmo.smusher;
30  
31  import java.util.Iterator;
32  import java.util.List;
33  
34  import org.openrdf.OpenRDFException;
35  import org.openrdf.elmo.sesame.SesameManager;
36  import org.openrdf.elmo.smusher.listener.SmusherListener;
37  import org.openrdf.model.Resource;
38  import org.openrdf.query.BindingSet;
39  import org.openrdf.query.TupleQueryResult;
40  import org.openrdf.repository.Repository;
41  import org.openrdf.repository.RepositoryConnection;
42  import org.slf4j.Logger;
43  import org.slf4j.LoggerFactory;
44  
45  
46  public class FixedQuerySmusher extends AbstractSmusher {
47     
48      protected String _query = "";
49      protected final static Logger _logger = LoggerFactory.getLogger(FixedQuerySmusher.class);
50     
51      public FixedQuerySmusher(String query) {
52          _query = query;
53      }
54      
55      public void smush(SesameManager firstRepository, SesameManager secondRepository) throws OpenRDFException {
56           //Start all the registered listeners
57         Iterator it = _listeners.iterator();
58         while (it.hasNext()) {
59             SmusherListener nextListener = (SmusherListener) it.next();
60             nextListener.start();
61         }
62         
63         //Works only on a single repository
64         if (!firstRepository.equals(secondRepository)) {
65          throw new IllegalArgumentException("FixedQuerySmusher works only if there is a single repository.");
66         }
67         
68         //Select with a single query all matching instances
69     	   RepositoryConnection con = firstRepository.getConnection();
70   	   TupleQueryResult result = null;
71         try {
72      	   result = con.prepareTupleQuery(org.openrdf.query.QueryLanguage.SERQL,
73  					_query).evaluate();
74       	   List<String> bindingNames = result.getBindingNames();
75      
76      	   int count = 0;
77      	   while (result.hasNext()) {
78         			BindingSet bindings = result.next();
79         		 if (_logger.isDebugEnabled()) {
80                     if ((count++ + 1) % 10000 == 0) {
81                         _logger.debug("Processed 10000 instances"); 
82                     }
83                 }
84    
85         		  Resource firstValue = (Resource) bindings.getValue(bindingNames.get(0)); 
86                Resource secondValue = (Resource) bindings.getValue(bindingNames.get(1)); 
87                Iterator subit = _listeners.iterator();
88                while (subit.hasNext()) {
89                     SmusherListener nextListener = (SmusherListener) subit.next();
90                     nextListener.matchFound(firstValue, secondValue);    
91                }
92             }        
93         }  finally {
94  			if (result != null) result.close();
95  			if (con != null) con.close();
96         }
97         
98         //Finish all the registered listeners
99         it = _listeners.iterator();
100        while (it.hasNext()) {
101            SmusherListener nextListener = (SmusherListener) it.next();
102            nextListener.finish();
103        }
104     }
105 }