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1   /*
2    * $Header$
3    * $Revision: 1261 $
4    * $Date: 2006-11-30 10:49:27 -0800 (Thu, 30 Nov 2006) $
5    *
6    * ====================================================================
7    *
8    * Copyright 2000-2002 bob mcwhirter & James Strachan.
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 are
13   * met:
14   * 
15   *   * Redistributions of source code must retain the above copyright
16   *     notice, this list of conditions and the following disclaimer.
17   * 
18   *   * Redistributions in binary form must reproduce the above copyright
19   *     notice, this list of conditions and the following disclaimer in the
20   *     documentation and/or other materials provided with the distribution.
21   * 
22   *   * Neither the name of the Jaxen Project nor the names of its
23   *     contributors may be used to endorse or promote products derived 
24   *     from this software without specific prior written permission.
25   * 
26   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
27   * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28   * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
29   * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
30   * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
31   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
32   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
33   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
34   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
35   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
36   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37   *
38   * ====================================================================
39   * This software consists of voluntary contributions made by many 
40   * individuals on behalf of the Jaxen Project and was originally 
41   * created by bob mcwhirter <bob@werken.com> and 
42   * James Strachan <jstrachan@apache.org>.  For more information on the 
43   * Jaxen Project, please see <http://www.jaxen.org/>.
44   * 
45   * $Id: DefaultVariableReferenceExpr.java 1261 2006-11-30 18:49:27Z elharo $
46   */
47  
48  package org.jaxen.expr;
49  
50  import org.jaxen.Context;
51  import org.jaxen.UnresolvableException;
52  
53  class DefaultVariableReferenceExpr extends DefaultExpr implements VariableReferenceExpr
54  {
55      /**
56       * 
57       */
58      private static final long serialVersionUID = 8832095437149358674L;
59      private String prefix;
60      private String localName;
61  
62      DefaultVariableReferenceExpr(String prefix,
63                                          String variableName)
64      {
65          this.prefix       = prefix;
66          this.localName = variableName;
67      }
68  
69      public String getPrefix()
70      {
71          return this.prefix;
72      }
73  
74      public String getVariableName()
75      {
76          return this.localName;
77      }
78  
79      public String toString()
80      {
81          return "[(DefaultVariableReferenceExpr): " + getQName() + "]";
82      }
83      
84      private String getQName() {
85          if ( "".equals(prefix) )
86          {
87              return localName;
88          }
89          return prefix + ":" + localName;
90      }
91  
92      public String getText()
93      {
94          return "$" + getQName();
95      }
96  
97      public Object evaluate(Context context)
98          throws UnresolvableException
99      {
100         String namespaceURI =
101             context.translateNamespacePrefixToUri( getPrefix() );
102 
103         return context.getVariableValue( namespaceURI,
104                                          prefix,
105                                          localName );
106     }
107     
108 }