View Javadoc

1   /*
2    * Copyright (c) 2007, James Leigh 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.sesame;
30  
31  import java.util.List;
32  
33  import org.openrdf.elmo.sesame.iterators.ElmoIteration;
34  import org.openrdf.query.Binding;
35  import org.openrdf.query.BindingSet;
36  import org.openrdf.query.TupleQueryResult;
37  
38  /**
39   * Converts the repository result into a single Bean.
40   * 
41   * @author James Leigh
42   * 
43   */
44  public class ElmoSingleQueryResult extends ElmoIteration<BindingSet, Object> {
45  
46  	private List<String> bindings;
47  
48  	private SesameManager manager;
49  
50  	private int maxResults;
51  
52  	private int position;
53  
54  	public ElmoSingleQueryResult(SesameManager manager, TupleQueryResult result, int maxResults) {
55  		super(result);
56  		bindings = result.getBindingNames();
57  		this.manager = manager;
58  		this.maxResults = maxResults;
59  	}
60  
61  	@Override
62  	protected Object convert(BindingSet sol) {
63  		Binding binding = sol.getBinding(bindings.get(0));
64  		return manager.getInstance(binding.getValue());
65  	}
66  
67  	@Override
68  	public boolean hasNext() {
69  		if (maxResults > 0 && position >= maxResults) {
70  			close();
71  			return false;
72  		}
73  		return super.hasNext();
74  	}
75  
76  	@Override
77  	public Object next() {
78  		try {
79  			position++;
80  			return super.next();
81  		} finally {
82  			if (maxResults > 0 && position >= maxResults) {
83  				close();
84  			}
85  		}
86  	}
87  
88  }