1   /*
2    * $Header$
3    * $Revision$
4    * $Date$
5    *
6    * ====================================================================
7    *
8    * Copyright (C) 2005 Elliotte Rusty Harold.
9    * All rights reserved.
10   *
11   * Redistribution and use in source and binary forms, with or without
12   * modification, are permitted provided that the following conditions
13   * are met:
14   * 
15   * 1. Redistributions of source code must retain the above copyright
16   *    notice, this list of conditions, and the following disclaimer.
17   *
18   * 2. Redistributions in binary form must reproduce the above copyright
19   *    notice, this list of conditions, and the disclaimer that follows 
20   *    these conditions in the documentation and/or other materials 
21   *    provided with the distribution.
22   *
23   * 3. The name "Jaxen" must not be used to endorse or promote products
24   *    derived from this software without prior written permission.  For
25   *    written permission, please contact license@jaxen.org.
26   * 
27   * 4. Products derived from this software may not be called "Jaxen", nor
28   *    may "Jaxen" appear in their name, without prior written permission
29   *    from the Jaxen Project Management (pm@jaxen.org).
30   * 
31   * In addition, we request (but do not require) that you include in the 
32   * end-user documentation provided with the redistribution and/or in the 
33   * software itself an acknowledgement equivalent to the following:
34   *     "This product includes software developed by the
35   *      Jaxen Project (http://www.jaxen.org/)."
36   * Alternatively, the acknowledgment may be graphical using the logos 
37   * available at http://www.jaxen.org/
38   *
39   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
40   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
41   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
42   * DISCLAIMED.  IN NO EVENT SHALL THE Jaxen AUTHORS OR THE PROJECT
43   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
45   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
46   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
47   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
48   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
49   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50   * SUCH DAMAGE.
51   *
52   * ====================================================================
53   * This software consists of voluntary contributions made by many 
54   * individuals on behalf of the Jaxen Project and was originally 
55   * created by bob mcwhirter <bob@werken.com> and 
56   * James Strachan <jstrachan@apache.org>.  For more information on the 
57   * Jaxen Project, please see <http://www.jaxen.org/>.
58   * 
59   * $Id$
60   */
61  
62  package org.jaxen.function;
63  
64  import java.util.Iterator;
65  import java.util.List;
66  
67  import javax.xml.parsers.DocumentBuilder;
68  import javax.xml.parsers.DocumentBuilderFactory;
69  import javax.xml.parsers.ParserConfigurationException;
70  
71  import junit.framework.TestCase;
72  
73  import org.jaxen.*;
74  import org.jaxen.dom.DOMXPath;
75  import org.w3c.dom.Document;
76  
77  /***
78   * @author Elliotte Rusty Harold
79   *
80   */
81  public class ExtensionFunctionTest extends TestCase {
82  
83      private Document doc;
84      
85      public void setUp() throws ParserConfigurationException
86      {
87          DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
88          factory.setNamespaceAware(true);
89          DocumentBuilder builder = factory.newDocumentBuilder();
90          doc = builder.newDocument();
91      }
92  
93  
94      public ExtensionFunctionTest(String name) {
95          super(name);
96      }
97      
98      class MinFunction implements Function {
99  
100         public Object call(Context context, List args) {
101             
102             if (args.isEmpty()) return new Double(Double.NaN);
103             
104             Navigator navigator = context.getNavigator();
105             double min = Double.MAX_VALUE;
106             Iterator iterator = args.iterator();
107             while (iterator.hasNext()) {
108                 double next = NumberFunction.evaluate(iterator.next(), navigator).doubleValue();
109                 min = Math.min(min, next);
110             }
111             return new Double(min);
112         }
113         
114     }
115     
116     
117     public void testRegisterExtensionFunction() throws JaxenException {
118         
119         SimpleFunctionContext fc = new XPathFunctionContext(false);
120         fc.registerFunction("http://exslt.org/math", "min", new MinFunction());
121         
122         SimpleNamespaceContext nc = new SimpleNamespaceContext();
123         nc.addNamespace("math", "http://exslt.org/math");
124         
125         BaseXPath xpath = new DOMXPath("math:min(//x)");
126         
127         xpath.setFunctionContext(fc);
128         xpath.setNamespaceContext(nc);
129         
130         org.w3c.dom.Element a = doc.createElementNS("", "a");
131         org.w3c.dom.Element b = doc.createElementNS("", "b");
132         doc.appendChild(a);
133         a.appendChild(b);
134         org.w3c.dom.Element x2 = doc.createElementNS("", "x");
135         org.w3c.dom.Element x3 = doc.createElementNS("", "x");
136         org.w3c.dom.Element x4 = doc.createElementNS("", "x");
137         a.appendChild(x4);
138         b.appendChild(x2);
139         b.appendChild(x3);
140         x2.appendChild(doc.createTextNode("2"));
141         x3.appendChild(doc.createTextNode("3"));
142         x4.appendChild(doc.createTextNode("4"));
143         
144         Double result = (Double) xpath.evaluate(doc);
145         assertEquals(new Double(2), result);
146        
147         
148     }
149     
150 
151 }