1 /*
2 * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/SimpleVariableContext.java,v 1.19 2006/06/03 20:19:54 elharo Exp $
3 * $Revision: 1.19 $
4 * $Date: 2006/06/03 20:19:54 $
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: SimpleVariableContext.java,v 1.19 2006/06/03 20:19:54 elharo Exp $
46 */
47
48
49 package org.jaxen;
50
51 import java.io.Serializable;
52 import java.util.HashMap;
53 import java.util.Map;
54
55 /*** Simple default implementation for <code>VariableContext</code>.
56 *
57 * <p>
58 * This is a simple table-based key-lookup implementation
59 * for <code>VariableContext</code> which can be programmatically
60 * extended by setting additional variables.
61 * </p>
62 *
63 * @author <a href="mailto:bob@werken.com">bob mcwhirter</a>
64 */
65 public class SimpleVariableContext implements VariableContext, Serializable
66 {
67 /***
68 *
69 */
70 private static final long serialVersionUID = 961322093794516518L;
71 /*** Table of variable bindings. */
72 private Map variables;
73
74 /*** Construct.
75 *
76 * <p>
77 * Create a new empty variable context.
78 * </p>
79 */
80 public SimpleVariableContext()
81 {
82 variables = new HashMap();
83 }
84
85 /*** Set the value associated with a variable.
86 *
87 * <p>
88 * This method sets a variable that is
89 * associated with a particular namespace.
90 * These variables appear such as <code>$prefix:foo</code>
91 * in an XPath expression. Prefix to URI resolution
92 * is the responsibility of a <code>NamespaceContext</code>.
93 * Variables within a <code>VariableContext</code> are
94 * referred to purely based upon their namespace URI,
95 * if any.
96 * </p>
97 *
98 * @param namespaceURI the namespace URI of the variable
99 * @param localName the local name of the variable
100 * @param value The value to be bound to the variable
101 */
102 public void setVariableValue( String namespaceURI,
103 String localName,
104 Object value )
105 {
106 this.variables.put( new QualifiedName(namespaceURI, localName),
107 value );
108 }
109
110 /*** Set the value associated with a variable.
111 *
112 * <p>
113 * This method sets a variable that is <strong>not</strong>
114 * associated with any particular namespace.
115 * These variables look like <code>$foo</code>
116 * in an XPath expression.
117 * </p>
118 *
119 * @param localName the local name of the variable
120 * @param value the value to be bound to the variable
121 */
122 public void setVariableValue( String localName,
123 Object value )
124 {
125 this.variables.put( new QualifiedName(null, localName), value );
126 }
127
128 public Object getVariableValue( String namespaceURI,
129 String prefix,
130 String localName )
131 throws UnresolvableException
132 {
133 QualifiedName key = new QualifiedName( namespaceURI, localName );
134
135 if ( this.variables.containsKey(key) )
136 {
137 return this.variables.get( key );
138 }
139 else
140 {
141 throw new UnresolvableException( "Variable " + key.getClarkForm() );
142 }
143 }
144 }