001 package org.apache.turbine.services.localization;
002
003 /*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements. See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership. The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License. You may obtain a copy of the License at
011 *
012 * http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied. See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022 import java.util.Locale;
023 import java.util.MissingResourceException;
024
025 import org.apache.commons.logging.Log;
026 import org.apache.commons.logging.LogFactory;
027 import org.apache.fulcrum.localization.LocalizationService;
028 import org.apache.turbine.services.InstantiationException;
029 import org.apache.turbine.services.TurbineServices;
030 import org.apache.turbine.services.pull.ApplicationTool;
031 import org.apache.turbine.util.RunData;
032 /**
033 * A pull tool which provides lookups for localized text by delegating
034 * to the configured Fulcrum <code>LocalizationService</code>.
035 *
036 * @author <a href="mailto:epugh@upstate.com">Eric Pugh</a>
037 * @author <a href="mailto:dlr@collab.net">Daniel Rall</a>
038 * @author <a href="mailto:jon@collab.net">Jon Stevens</a>
039 */
040 public class LocalizationTool implements ApplicationTool
041 {
042 /** Logging */
043 private static Log log = LogFactory.getLog(LocalizationTool.class);
044 /** Fulcrum Localization component */
045 private LocalizationService localizationService;
046 /**
047 * The language and country information parsed from the request's
048 * <code>Accept-Language</code> header. Reset on each request.
049 */
050 protected Locale locale;
051
052 /**
053 * Lazy load the LocalizationService.
054 * @return a fulcrum LocalizationService
055 */
056 public LocalizationService getLocalizationService()
057 {
058 if (localizationService == null)
059 {
060 try
061 {
062 localizationService = (LocalizationService)TurbineServices.getInstance()
063 .getService(LocalizationService.ROLE);
064 }
065 catch (Exception e)
066 {
067 throw new InstantiationException("Problem looking up Localization Service:"+e.getMessage());
068 }
069 }
070 return localizationService;
071 }
072
073 /**
074 * Creates a new instance. Used by <code>PullService</code>.
075 */
076 public LocalizationTool()
077 {
078 refresh();
079 }
080
081 /**
082 * <p>Performs text lookups for localization.</p>
083 *
084 * <p>Assuming there is a instance of this class with a HTTP
085 * request set in your template's context named <code>l10n</code>,
086 * the VTL <code>$l10n.HELLO</code> would render to
087 * <code>hello</code> for English requests and <code>hola</code>
088 * in Spanish (depending on the value of the HTTP request's
089 * <code>Accept-Language</code> header).</p>
090 *
091 * @param key The identifier for the localized text to retrieve.
092 * @return The localized text.
093 */
094 public String get(String key)
095 {
096 try
097 {
098 return getLocalizationService().getString(getBundleName(null), getLocale(), key);
099 }
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 object.
133 *
134 * @param key The identifier for the localized text to retrieve,
135 * @param arg1 The object to use as {0} when formatting the localized text.
136 * @return Formatted localized text.
137 * @see #format(String, Locale, String, Object[])
138 */
139 public String format(String key, Object arg1)
140 {
141 return getLocalizationService()
142 .format(getBundleName(null), getLocale(), key, arg1);
143 }
144
145 /**
146 * Formats a localized value using the provided objects.
147 *
148 * @param key The identifier for the localized text to retrieve,
149 * @param arg1 The object to use as {0} when formatting the localized text.
150 * @param arg2 The object to use as {1} when formatting the localized text.
151 * @return Formatted localized text.
152 * @see #format(String, Locale, String, Object[])
153 */
154 public String format(String key, Object arg1, Object arg2)
155 {
156 return getLocalizationService()
157 .format(getBundleName(null), getLocale(), key, arg1, arg2);
158 }
159
160 /**
161 * Formats a localized value using the provided objects.
162 *
163 * @param key The identifier for the localized text to retrieve,
164 * @param args The objects to use as {0}, {1}, etc. when
165 * formatting the localized text.
166 * @return Formatted localized text.
167 */
168 public String format(String key, Object[] args)
169 {
170 return getLocalizationService()
171 .format(getBundleName(null), getLocale(), key, args);
172 }
173
174 // ApplicationTool implementation
175
176 /**
177 * Sets the request to get the <code>Accept-Language</code> header
178 * from (reset on each request).
179 */
180 public void init(Object data)
181 {
182 if (data instanceof RunData)
183 {
184 // Pull necessary information out of RunData while we have
185 // a reference to it.
186 locale = getLocalizationService().getLocale(((RunData) data).getRequest());
187 }
188 }
189
190 /**
191 * No-op.
192 */
193 public void refresh()
194 {
195 locale = null;
196 }
197 }