1 /*
2 * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/SimpleNamespaceContext.java,v 1.15 2005/06/28 13:44:44 elharo Exp $
3 * $Revision: 1.15 $
4 * $Date: 2005/06/28 13:44:44 $
5 *
6 * ====================================================================
7 *
8 * Copyright (C) 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
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: SimpleNamespaceContext.java,v 1.15 2005/06/28 13:44:44 elharo Exp $
60 */
61
62
63 package org.jaxen;
64
65 import java.io.Serializable;
66 import java.util.HashMap;
67 import java.util.Iterator;
68 import java.util.Map;
69
70 /***
71 * Provides mappings from namespace prefix to namespace URI to the XPath
72 * engine.
73 */
74 public class SimpleNamespaceContext implements NamespaceContext, Serializable
75 {
76
77 // XXX should this prebind the xml prefix?
78 private Map namespaces;
79
80 /***
81 * Creates a new empty namespace context.
82 */
83 public SimpleNamespaceContext()
84 {
85 this.namespaces = new HashMap();
86 }
87
88 /***
89 * Creates a new namespace context pre-populated with the specified bindings.
90 *
91 * @param namespaces the initial namespace bindings in scope. The keys in this
92 * must be strings containing the prefixes and the values are strings
93 * containing the namespace URIs.
94 *
95 * @throws NullPointerException if the argument is null
96 */
97 public SimpleNamespaceContext(Map namespaces)
98 {
99 // FIXME this is dangerous. We should check that
100 // the contents are strings.
101 this.namespaces = new HashMap(namespaces);
102 }
103
104 /***
105 * Adds all the namespace declarations that are in scope on the given
106 * element. In the case of an XSLT stylesheet, this would be the element
107 * that has the XPath expression in one of its attributes; e.g.
108 * <code><xsl:if test="condition/xpath/expression"></code>.
109 *
110 * @param nav the navigator for use in conjunction with
111 * <code>element</code>
112 * @param element the element to copy the namespaces from
113 * @throws UnsupportedAxisException if the navigator does not support the
114 * namespace axis
115 */
116 public void addElementNamespaces( Navigator nav, Object element )
117 throws UnsupportedAxisException
118 {
119 Iterator namespaceAxis = nav.getNamespaceAxisIterator( element );
120
121 while ( namespaceAxis.hasNext() ) {
122 Object namespace = namespaceAxis.next();
123 String prefix = nav.getNamespacePrefix( namespace );
124 String uri = nav.getNamespaceStringValue( namespace );
125 if ( translateNamespacePrefixToUri(prefix) == null ) {
126 addNamespace( prefix, uri );
127 }
128 }
129 }
130
131 // ???? What if prefix or URI is null, or both?
132 /***
133 * Binds a prefix to a URI in this context.
134 *
135 * @param prefix the namespace prefix
136 * @param URI the namespace URI
137 */
138 public void addNamespace(String prefix, String URI)
139 {
140 this.namespaces.put( prefix, URI );
141 }
142
143 public String translateNamespacePrefixToUri(String prefix)
144 {
145 if ( this.namespaces.containsKey( prefix ) )
146 {
147 return (String) this.namespaces.get( prefix );
148 }
149
150 return null;
151 }
152 }