Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
LangFunction |
|
| 3.4;3.4 |
1 | /* | |
2 | * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/function/LangFunction.java,v 1.13 2006/02/05 21:47:41 elharo Exp $ | |
3 | * $Revision: 1.13 $ | |
4 | * $Date: 2006/02/05 21:47:41 $ | |
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: LangFunction.java,v 1.13 2006/02/05 21:47:41 elharo Exp $ | |
46 | */ | |
47 | ||
48 | ||
49 | package org.jaxen.function; | |
50 | ||
51 | import java.util.Iterator; | |
52 | import java.util.List; | |
53 | ||
54 | import org.jaxen.Context; | |
55 | import org.jaxen.Function; | |
56 | import org.jaxen.FunctionCallException; | |
57 | import org.jaxen.Navigator; | |
58 | import org.jaxen.UnsupportedAxisException; | |
59 | ||
60 | /** | |
61 | * <p> | |
62 | * <b>4.3</b> <code><i>boolean</i> lang(<i>string</i>)</code> | |
63 | * </p> | |
64 | * | |
65 | * <blockquote src="http://www.w3.org/TR/xpath#function-lang"> | |
66 | * <p> | |
67 | * The <b>lang</b> function returns true or false depending on whether | |
68 | * the language of the context node as specified by | |
69 | * <code>xml:lang</code> attributes is the same as or is a sublanguage | |
70 | * of the language specified by the argument string. The language of the | |
71 | * context node is determined by the value of the <code>xml:lang</code> | |
72 | * | |
73 | * attribute on the context node, or, if the context node has no | |
74 | * <code>xml:lang</code> attribute, by the value of the | |
75 | * <code>xml:lang</code> attribute on the nearest ancestor of the | |
76 | * context node that has an <code>xml:lang</code> attribute. If there | |
77 | * is no such attribute, then <b><a href="#function-lang">lang</a></b> | |
78 | * returns false. If there is such an attribute, then <b><a | |
79 | * href="#function-lang">lang</a></b> returns true if the attribute | |
80 | * value is equal to the argument ignoring case, or if there is some | |
81 | * suffix starting with <code>-</code> such that the attribute value | |
82 | * is equal to the argument ignoring that suffix of the attribute value | |
83 | * and ignoring case. For example, <code>lang("en")</code> would | |
84 | * return true if the context node is any of these five elements: | |
85 | * </p> | |
86 | * | |
87 | * <pre> | |
88 | * <para xml:lang="en"/> | |
89 | * <div xml:lang="en"><para/></div> | |
90 | * <para xml:lang="EN"/> | |
91 | * <para xml:lang="en-us"/> | |
92 | * </pre> | |
93 | * | |
94 | * </blockquote> | |
95 | * | |
96 | * @author Attila Szegedi (szegedia @ freemail.hu) | |
97 | * @see <a href="http://www.w3.org/TR/xpath#function-lang" | |
98 | * target="_top">XPath Specification</a> | |
99 | */ | |
100 | public class LangFunction implements Function | |
101 | { | |
102 | private static final String LANG_LOCALNAME = "lang"; | |
103 | private static final String XMLNS_URI = | |
104 | "http://www.w3.org/XML/1998/namespace"; | |
105 | ||
106 | ||
107 | /** | |
108 | * Create a new <code>LangFunction</code> object. | |
109 | */ | |
110 | 106 | public LangFunction() {} |
111 | ||
112 | ||
113 | /** | |
114 | * <p> | |
115 | * Determines whether or not the context node is written in the language specified | |
116 | * by the XPath string-value of <code>args.get(0)</code>, | |
117 | * as determined by the nearest <code>xml:lang</code> attribute in scope. | |
118 | * </p> | |
119 | * | |
120 | * @param context the context in which to evaluate the <code>lang()</code> function | |
121 | * @param args the arguments to the lang function | |
122 | * @return a <code>Boolean</code> indicating whether the context node is written in | |
123 | * the specified language | |
124 | * @throws FunctionCallException if <code>args</code> does not have length one | |
125 | * | |
126 | */ | |
127 | public Object call(Context context, | |
128 | List args) throws FunctionCallException | |
129 | { | |
130 | 322 | if (args.size() != 1) { |
131 | 4 | throw new FunctionCallException("lang() requires exactly one argument."); |
132 | } | |
133 | ||
134 | 318 | Object arg = args.get(0); |
135 | ||
136 | try { | |
137 | 318 | return evaluate(context.getNodeSet(), arg, context.getNavigator() ); |
138 | } | |
139 | 0 | catch(UnsupportedAxisException e) { |
140 | 0 | throw new FunctionCallException("Can't evaluate lang()", |
141 | e); | |
142 | } | |
143 | ||
144 | } | |
145 | ||
146 | private static Boolean evaluate(List contextNodes, Object lang, Navigator nav) | |
147 | throws UnsupportedAxisException | |
148 | { | |
149 | 318 | return evaluate(contextNodes.get(0), |
150 | StringFunction.evaluate(lang, nav), nav) | |
151 | ? Boolean.TRUE : Boolean.FALSE; | |
152 | } | |
153 | ||
154 | private static boolean evaluate(Object node, String lang, Navigator nav) | |
155 | throws UnsupportedAxisException | |
156 | { | |
157 | ||
158 | 318 | Object element = node; |
159 | 318 | if (! nav.isElement(element)) { |
160 | 8 | element = nav.getParentNode(node); |
161 | } | |
162 | 564 | while (element != null && nav.isElement(element)) |
163 | { | |
164 | 532 | Iterator attrs = nav.getAttributeAxisIterator(element); |
165 | 532 | while(attrs.hasNext()) |
166 | { | |
167 | 286 | Object attr = attrs.next(); |
168 | 286 | if(LANG_LOCALNAME.equals(nav.getAttributeName(attr)) && |
169 | XMLNS_URI.equals(nav.getAttributeNamespaceUri(attr))) | |
170 | { | |
171 | 286 | return |
172 | isSublang(nav.getAttributeStringValue(attr), lang); | |
173 | } | |
174 | 0 | } |
175 | 246 | element = nav.getParentNode(element); |
176 | 246 | } |
177 | 32 | return false; |
178 | } | |
179 | ||
180 | private static boolean isSublang(String sublang, String lang) | |
181 | { | |
182 | 286 | if(sublang.equalsIgnoreCase(lang)) |
183 | { | |
184 | 38 | return true; |
185 | } | |
186 | 248 | int ll = lang.length(); |
187 | 248 | return |
188 | sublang.length() > ll && | |
189 | sublang.charAt(ll) == '-' && | |
190 | sublang.substring(0, ll).equalsIgnoreCase(lang); | |
191 | } | |
192 | ||
193 | } | |
194 |