Java tutorial
/* This file is part of Cyclos (www.cyclos.org). A project of the Social Trade Organisation (www.socialtrade.org). Cyclos is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. Cyclos is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Cyclos; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ package nl.strohalm.cyclos.struts; import java.util.ArrayList; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Properties; import java.util.concurrent.Callable; import javax.servlet.ServletContext; import nl.strohalm.cyclos.services.customization.TranslationChangeListener; import nl.strohalm.cyclos.services.customization.TranslationMessageService; import nl.strohalm.cyclos.utils.MessageResourcesLoadedListener; import nl.strohalm.cyclos.utils.access.LoggedUser; import org.apache.commons.lang.StringUtils; import org.apache.struts.Globals; import org.apache.struts.util.MessageResources; import org.springframework.web.context.ServletContextAware; /** * Customized message resources used to get data from the service * @author luis */ public class CyclosMessageResources extends MessageResources implements ServletContextAware { private static final long serialVersionUID = 6706539088478972L; private ServletContext servletContext; private TranslationMessageService translationMessageService; private Properties properties; private List<MessageResourcesLoadedListener> messagesLoadedListeners = new ArrayList<MessageResourcesLoadedListener>(); public CyclosMessageResources() { super(null, null); } public void addMessagesLoadedListener(final MessageResourcesLoadedListener messagesLoadedListener) { messagesLoadedListeners.add(messagesLoadedListener); } @Override public String getMessage(final Locale locale, final String key) { String message = getProperties().getProperty(key); if (message == null) { message = "???" + key + "???"; } return message; } /** * Creates and initializes an instance for the given servlet context */ public void initialize() { // Read the messages of the language, creating missing keys translationMessageService.addTranslationChangeListener(new TranslationChangeListener() { @Override public void onTranslationsChanged(final Properties properties) { reload(properties); } }); // Load the messages reload(null); // now we can fire an event saying that the translation resources have been loaded for (final MessageResourcesLoadedListener messagesLoadedListener : messagesLoadedListeners) { messagesLoadedListener.onApplicationResourcesLoaded(); } // Store the resources on the context, so Struts will find it servletContext.setAttribute(Globals.MESSAGES_KEY, this); } @Override public void setServletContext(final ServletContext context) { servletContext = context; } public void setTranslationMessageService(final TranslationMessageService translationMessageService) { this.translationMessageService = translationMessageService; } private Properties getProperties() { if (properties == null) { reload(null); } return properties; } private synchronized void reload(final Properties newProperties) { properties = LoggedUser.runAsSystem(new Callable<Properties>() { @Override public Properties call() throws Exception { // First, read the English properties, to ensure defaults final Properties properties = translationMessageService.readFile(Locale.US); // Then load all properties from DB final Properties dbProperties = newProperties == null ? translationMessageService.exportAsProperties() : newProperties; for (final Map.Entry<Object, Object> entry : dbProperties.entrySet()) { final String key = (String) entry.getKey(); final String value = (String) entry.getValue(); if (StringUtils.isNotEmpty(value)) { properties.setProperty(key, value); } } return properties; } }); // Clear the Struts cache formats.clear(); } }