Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
WebappXMLResources |
|
| 5.0;5 |
1 | /* | |
2 | * $Id: WebappXMLResources.java 348371 2005-11-23 04:56:51Z niallp $ | |
3 | * $Revision: 348371 $ | |
4 | * $Date: 2005-11-23 04:56:51 +0000 (Wed, 23 Nov 2005) $ | |
5 | * | |
6 | * ==================================================================== | |
7 | * | |
8 | * Copyright 2003-2005 The Apache Software Foundation | |
9 | * | |
10 | * Licensed under the Apache License, Version 2.0 (the "License"); | |
11 | * you may not use this file except in compliance with the License. | |
12 | * You may obtain a copy of the License at | |
13 | * | |
14 | * http://www.apache.org/licenses/LICENSE-2.0 | |
15 | * | |
16 | * Unless required by applicable law or agreed to in writing, software | |
17 | * distributed under the License is distributed on an "AS IS" BASIS, | |
18 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
19 | * See the License for the specific language governing permissions and | |
20 | * limitations under the License. | |
21 | * | |
22 | */ | |
23 | ||
24 | package org.apache.commons.resources.impl; | |
25 | ||
26 | import java.io.FileNotFoundException; | |
27 | import java.io.IOException; | |
28 | import java.io.InputStream; | |
29 | import java.util.HashMap; | |
30 | import java.util.Locale; | |
31 | import java.util.Map; | |
32 | ||
33 | import javax.servlet.ServletContext; | |
34 | ||
35 | import org.apache.commons.digester.Digester; | |
36 | import org.apache.commons.logging.Log; | |
37 | import org.apache.commons.logging.LogFactory; | |
38 | import org.xml.sax.SAXException; | |
39 | ||
40 | /** | |
41 | * <p>Concrete implementation of | |
42 | * {@link org.apache.commons.resources.Resources} that wraps a family | |
43 | * (one per <code>Locale</code> of XML documents that share a base | |
44 | * context-relative path for servlet context resources, and have | |
45 | * name suffixes reflecting the <code>Locale</code> for which | |
46 | * the document's messages apply. Resources are looked up in a hierarchy | |
47 | * of properties files in a manner identical to that performed by | |
48 | * <code>java.util.ResourceBundle.getBundle().</code>.</p> | |
49 | * | |
50 | * <p>The base resource path passed to our constructor must contain the | |
51 | * context-relative base name of the properties file family. | |
52 | * For example, if the base path is passed as | |
53 | * <code>http://localhost/foo/Bar</code>, the resources for the | |
54 | * <code>en_US</code> Locale would be stored under URL | |
55 | * <code>http://localhost/foo/Bar_en_US.xml</code>, and the default | |
56 | * resources would be stored in | |
57 | * <code>http://localhost/foo/Bar.xml</code>.</p> | |
58 | */ | |
59 | public class WebappXMLResources extends CollectionResourcesBase { | |
60 | ||
61 | /** | |
62 | * <p>The <code>Log</code> instance for this class.</p> | |
63 | */ | |
64 | 0 | private transient Log log = LogFactory.getLog(WebappXMLResources.class); |
65 | ||
66 | /** | |
67 | * <p>Create a new {@link org.apache.commons.resources.Resources} instance with the specified | |
68 | * logical name and base resource URL.</p> | |
69 | * | |
70 | * @param name Logical name of the new instance | |
71 | * @param base Base URL of the family of properties files that contain | |
72 | * the resource keys and values | |
73 | * @param servletContext the <code>ServletContext</code> instance | |
74 | * to use for resolving resource references | |
75 | */ | |
76 | public WebappXMLResources(String name, String base, | |
77 | ServletContext servletContext) { | |
78 | ||
79 | 0 | super(name, base); |
80 | 0 | this.servletContext = servletContext; |
81 | ||
82 | 0 | } |
83 | ||
84 | ||
85 | // ----------------------------------------------------- Instance Variables | |
86 | ||
87 | /** | |
88 | * <p>The <code>ServletContext</code> instance for resolving | |
89 | * our resources references.</p> | |
90 | */ | |
91 | 0 | private ServletContext servletContext = null; |
92 | ||
93 | ||
94 | // ------------------------------------------------------ Protected Methods | |
95 | ||
96 | ||
97 | /** | |
98 | * <p>Return a <code>Map</code> containing the name-value mappings for | |
99 | * the specified base URL and requested <code>Locale</code>, if there | |
100 | * are any. If there are no defined mappings for the specified | |
101 | * <code>Locale</code>, return an empty <code>Map</code> instead.</p> | |
102 | * | |
103 | * <p>Concrete subclasses must override this method to perform the | |
104 | * appropriate lookup. A typical implementation will construct an | |
105 | * absolute URL based on the specified base URL and <code>Locale</code>, | |
106 | * retrieve the specified resource file (if any), and parse it into | |
107 | * a <code>Map</code> structure.</p> | |
108 | * | |
109 | * <p>Caching of previously retrieved <code>Map</code>s (if any) should | |
110 | * be performed by callers of this method. Therefore, this method should | |
111 | * always attempt to retrieve the specified resource and load it | |
112 | * appropriately.</p> | |
113 | * | |
114 | * @param baseUrl Base URL of the resource files for this {@link org.apache.commons.resources.Resources} | |
115 | * instance | |
116 | * @param locale <code>Locale</code> for which name-value mappings | |
117 | * are requested | |
118 | * @return A name-value Map for the specified URL and locale. | |
119 | */ | |
120 | protected Map getLocaleMap(String baseUrl, Locale locale) { | |
121 | ||
122 | 0 | if (getLog().isDebugEnabled()) { |
123 | 0 | getLog().debug("Loading locale '" + locale + "' resources from base '" + |
124 | baseUrl + "'"); | |
125 | } | |
126 | ||
127 | 0 | Map map = new HashMap(); |
128 | 0 | String name = baseUrl + getLocaleSuffix(locale) + ".xml"; |
129 | 0 | InputStream stream = null; |
130 | ||
131 | try { | |
132 | ||
133 | // Open an input stream to the URL for this locale (if any) | |
134 | 0 | if (getLog().isTraceEnabled()) { |
135 | 0 | getLog().trace("Complete path is '" + name + "'"); |
136 | } | |
137 | 0 | stream = servletContext.getResourceAsStream(name); |
138 | ||
139 | // Create and configure a new Digester instance | |
140 | 0 | if (stream != null) { |
141 | ||
142 | 0 | if (getLog().isTraceEnabled()) { |
143 | 0 | getLog().trace("Creating Digester instance"); |
144 | } | |
145 | 0 | Digester digester = new Digester(); |
146 | 0 | digester.setNamespaceAware(false); |
147 | 0 | digester.setValidating(false); |
148 | 0 | digester.push(map); |
149 | 0 | digester.addCallMethod("resources/resource", "put", 2, |
150 | new String[] { "java.lang.Object", | |
151 | "java.lang.Object" }); | |
152 | 0 | digester.addCallParam("resources/resource", 0, "id"); |
153 | 0 | digester.addCallParam("resources/resource", 1); |
154 | ||
155 | // Parse the input stream and populate the name-value mappings | |
156 | 0 | if (getLog().isTraceEnabled()) { |
157 | 0 | getLog().trace("Parsing input resource"); |
158 | } | |
159 | 0 | digester.parse(stream); |
160 | ||
161 | } | |
162 | ||
163 | 0 | } catch (FileNotFoundException e) { |
164 | ||
165 | // Log and swallow this exception | |
166 | 0 | if (getLog().isDebugEnabled()) { |
167 | 0 | getLog().debug("No resources for locale '" + locale + |
168 | "' from base '" + baseUrl + "'"); | |
169 | } | |
170 | 0 | map.clear(); |
171 | ||
172 | 0 | } catch (IOException e) { |
173 | ||
174 | // Log and swallow this exception | |
175 | 0 | getLog().warn("IOException loading locale '" + locale + |
176 | "' from base '" + baseUrl + "'", e); | |
177 | 0 | map.clear(); |
178 | ||
179 | 0 | } catch (SAXException e) { |
180 | ||
181 | // Log and swallow this exception | |
182 | 0 | getLog().warn("SAXException loading locale '" + locale + |
183 | "' from base '" + baseUrl + "'", e); | |
184 | 0 | map.clear(); |
185 | ||
186 | 0 | } finally { |
187 | ||
188 | // Close the input stream that was opened earlier | |
189 | 0 | if (stream != null) { |
190 | try { | |
191 | 0 | stream.close(); |
192 | 0 | } catch (Exception e) { |
193 | // standard io | |
194 | 0 | } |
195 | 0 | stream = null; |
196 | } | |
197 | ||
198 | 0 | } |
199 | ||
200 | // Return the populated (or empty) map | |
201 | 0 | return (map); |
202 | ||
203 | ||
204 | } | |
205 | ||
206 | /** | |
207 | * Accessor method for Log instance. | |
208 | * | |
209 | * The Log instance variable is transient and | |
210 | * accessing it through this method ensures it | |
211 | * is re-initialized when this instance is | |
212 | * de-serialized. | |
213 | * | |
214 | * @return The Log instance. | |
215 | */ | |
216 | private Log getLog() { | |
217 | 0 | if (log == null) { |
218 | 0 | log = LogFactory.getLog(WebappXMLResources.class); |
219 | } | |
220 | 0 | return log; |
221 | } | |
222 | ||
223 | } |