Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
VariableContext |
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| 1.0;1 |
1 | /* | |
2 | * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/VariableContext.java,v 1.11 2006/07/03 11:58:31 elharo Exp $ | |
3 | * $Revision: 1.11 $ | |
4 | * $Date: 2006/07/03 11:58:31 $ | |
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: VariableContext.java,v 1.11 2006/07/03 11:58:31 elharo Exp $ | |
46 | */ | |
47 | ||
48 | ||
49 | package org.jaxen; | |
50 | ||
51 | /** Resolves variable bindings within an XPath expression. | |
52 | * | |
53 | * <p> | |
54 | * Variables within an XPath expression are denoted using | |
55 | * notation such as <code>$varName</code> or | |
56 | * <code>$nsPrefix:varName</code>, and may | |
57 | * refer to a <code>Boolean</code>, <code>Double</code>, <code>String</code>, | |
58 | * node-set (<code>List</code>) or individual XML node. | |
59 | * </p> | |
60 | * | |
61 | * <p> | |
62 | * When a variable is bound to a node-set, the | |
63 | * actual Java object returned should be a <code>java.util.List</code> | |
64 | * containing XML nodes from the object-model (e.g. dom4j, JDOM, DOM, etc.) | |
65 | * being used with the XPath. | |
66 | * </p> | |
67 | * | |
68 | * <p> | |
69 | * A variable may validly be assigned the <code>null</code> value, | |
70 | * but an unbound variable (one that this context does not know about) | |
71 | * should cause an {@link UnresolvableException} to be thrown. | |
72 | * </p> | |
73 | * | |
74 | * <p> | |
75 | * Implementations of this interface should implement <code>Serializable</code>. | |
76 | * </p> | |
77 | * | |
78 | * @see SimpleVariableContext | |
79 | * @see NamespaceContext | |
80 | * | |
81 | * @author <a href="mailto:bob@werken.com">bob mcwhirter</a> | |
82 | * @author <a href="mailto:jstrachan@apache.org">James Strachan</a> | |
83 | */ | |
84 | public interface VariableContext | |
85 | { | |
86 | /** An implementation should return the value of an XPath variable | |
87 | * based on the namespace URI and local name of the variable-reference | |
88 | * expression. | |
89 | * | |
90 | * <p> | |
91 | * It must not use the prefix parameter to select a variable, | |
92 | * because a prefix could be bound to any namespace; the prefix parameter | |
93 | * could be used in debugging output or other generated information. | |
94 | * The prefix may otherwise be ignored. | |
95 | * </p> | |
96 | * | |
97 | * @param namespaceURI the namespace URI to which the prefix parameter | |
98 | * is bound in the XPath expression. If the variable | |
99 | * reference expression had no prefix, the namespace | |
100 | * URI is <code>null</code>. | |
101 | * @param prefix the prefix that was used in the variable reference | |
102 | * expression; this value is ignored and has no effect | |
103 | * @param localName the local name of the variable-reference | |
104 | * expression. If there is no prefix, then this is | |
105 | * the whole name of the variable. | |
106 | * | |
107 | * @return the variable's value (which can be <code>null</code>) | |
108 | * @throws UnresolvableException when the variable cannot be resolved | |
109 | */ | |
110 | public Object getVariableValue( String namespaceURI, | |
111 | String prefix, | |
112 | String localName ) | |
113 | throws UnresolvableException; | |
114 | } |