1 package org.apache.turbine.services.localization;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.util.Locale;
23 import java.util.MissingResourceException;
24
25 import org.apache.commons.logging.Log;
26 import org.apache.commons.logging.LogFactory;
27 import org.apache.fulcrum.localization.LocalizationService;
28 import org.apache.turbine.services.InstantiationException;
29 import org.apache.turbine.services.TurbineServices;
30 import org.apache.turbine.services.pull.ApplicationTool;
31 import org.apache.turbine.util.RunData;
32 /**
33 * A pull tool which provides lookups for localized text by delegating
34 * to the configured Fulcrum <code>LocalizationService</code>.
35 *
36 * @author <a href="mailto:epugh@upstate.com">Eric Pugh</a>
37 * @author <a href="mailto:dlr@collab.net">Daniel Rall</a>
38 * @author <a href="mailto:jon@collab.net">Jon Stevens</a>
39 */
40 public class LocalizationTool implements ApplicationTool
41 {
42 /** Logging */
43 private static Log log = LogFactory.getLog(LocalizationTool.class);
44 /** Fulcrum Localization component */
45 private LocalizationService localizationService;
46 /**
47 * The language and country information parsed from the request's
48 * <code>Accept-Language</code> header. Reset on each request.
49 */
50 protected Locale locale;
51
52 /**
53 * Lazy load the LocalizationService.
54 * @return a fulcrum LocalizationService
55 */
56 public LocalizationService getLocalizationService()
57 {
58 if (localizationService == null)
59 {
60 try
61 {
62 localizationService = (LocalizationService)TurbineServices.getInstance()
63 .getService(LocalizationService.ROLE);
64 }
65 catch (Exception e)
66 {
67 throw new InstantiationException("Problem looking up Localization Service:"+e.getMessage());
68 }
69 }
70 return localizationService;
71 }
72
73 /**
74 * Creates a new instance. Used by <code>PullService</code>.
75 */
76 public LocalizationTool()
77 {
78 refresh();
79 }
80
81 /**
82 * <p>Performs text lookups for localization.</p>
83 *
84 * <p>Assuming there is a instance of this class with a HTTP
85 * request set in your template's context named <code>l10n</code>,
86 * the VTL <code>$l10n.HELLO</code> would render to
87 * <code>hello</code> for English requests and <code>hola</code>
88 * in Spanish (depending on the value of the HTTP request's
89 * <code>Accept-Language</code> header).</p>
90 *
91 * @param key The identifier for the localized text to retrieve.
92 * @return The localized text.
93 */
94 public String get(String key)
95 {
96 try
97 {
98 return getLocalizationService().getString(getBundleName(null), getLocale(), key);
99 }
100 catch (MissingResourceException noKey)
101 {
102 log.error(noKey);
103 return null;
104 }
105 }
106
107 /**
108 * Gets the current locale.
109 *
110 * @return The locale currently in use.
111 */
112 public Locale getLocale()
113 {
114 return locale;
115 }
116
117 /**
118 * The return value of this method is used to set the name of the
119 * bundle used by this tool. Useful as a hook for using a
120 * different bundle than specified in your
121 * <code>LocalizationService</code> configuration.
122 *
123 * @param data The inputs passed from {@link #init(Object)}.
124 * (ignored by this implementation).
125 */
126 protected String getBundleName(Object data)
127 {
128 return getLocalizationService().getDefaultBundleName();
129 }
130
131 /**
132 * Formats a localized value using the provided objects.
133 *
134 * @param key The identifier for the localized text to retrieve,
135 * @param args The objects to use as {0}, {1}, etc. when
136 * formatting the localized text.
137 * @return Formatted localized text.
138 */
139 public String format(String key, Object... args)
140 {
141 return getLocalizationService()
142 .format(getBundleName(null), getLocale(), key, args);
143 }
144
145 // ApplicationTool implementation
146
147 /**
148 * Sets the request to get the <code>Accept-Language</code> header
149 * from (reset on each request).
150 */
151 @Override
152 public void init(Object data)
153 {
154 if (data instanceof RunData)
155 {
156 // Pull necessary information out of RunData while we have
157 // a reference to it.
158 locale = getLocalizationService().getLocale(((RunData) data).getRequest());
159 }
160 }
161
162 /**
163 * No-op.
164 */
165 @Override
166 public void refresh()
167 {
168 locale = null;
169 }
170 }