Java tutorial
/******************************************************************************* * Copyright (c) 2004, 2010 BREDEX GmbH. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * BREDEX GmbH - initial API and implementation and/or initial documentation *******************************************************************************/ package org.eclipse.jubula.tools.i18n; import java.io.ByteArrayInputStream; import java.io.IOException; import java.text.MessageFormat; import java.util.Enumeration; import java.util.HashMap; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.MissingResourceException; import java.util.PropertyResourceBundle; import java.util.ResourceBundle; import org.apache.commons.lang.StringUtils; import org.eclipse.jubula.tools.constants.StringConstants; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Class to internationalize all CompSystem strings * @author BREDEX GmbH * @created 02.01.2007 */ public class CompSystemI18n { /** the logger */ private static Logger log = LoggerFactory.getLogger(CompSystemI18n.class); /** List of ResourceBundles */ private static final List PLUGIN_BUNDLES = new LinkedList(); /** * mapping from i18n keys (String) to i18n values (String) */ private static final Map I18N_MAP = new HashMap(); /** * Constructor */ private CompSystemI18n() { // private constructor to prevent instantiation of class utility } /** * Adds the given {@link ResourceBundle} * @param bundle a {@link ResourceBundle} */ public static void addResourceBundle(ResourceBundle bundle) { if (bundle == null) { log.error("ResourceBundle is null!"); //$NON-NLS-1$ return; } PLUGIN_BUNDLES.add(bundle); } /** * Gets the internationalized String by a given key. * * @param key * the key for the internationalized String. * @return a internationalized <code>String</code>. */ public static String getString(String key) { return getString(key, false); } /** * Gets the internationalized String by a given key. * * @param key * the key for the internationalized String. * @param fallBack * returns the key if no value found * @return a internationalized <code>String</code>. */ public static String getString(String key, boolean fallBack) { try { return getStringInternal(key); } catch (MissingResourceException mre) { if (!fallBack) { logError(key, mre); } } return key; } /** * Logs in error log * * @param key * the I18n-key * @param throwable * the throwable */ private static void logError(String key, Throwable throwable) { log.error("Cannot find I18N-key in resource bundles: " + key, throwable); //$NON-NLS-1$ } /** * Searches for the value of the given key in all bundles.<br> * throws MissingResourceException if the key was not found. * @param key the key * @return the value for the given key */ private static String getStringInternal(String key) { if (key == null) { return StringUtils.EMPTY; } String value = (String) I18N_MAP.get(key); if (value != null) { return value; } Iterator bundleIter = PLUGIN_BUNDLES.iterator(); while (bundleIter.hasNext()) { ResourceBundle bundle = (ResourceBundle) bundleIter.next(); try { value = bundle.getString(key); I18N_MAP.put(key, value); return value; } catch (MissingResourceException ex) { // ok here, we search in multiple bundles } } I18N_MAP.put(key, key); throw new MissingResourceException("No entry found for key: " + key, //$NON-NLS-1$ CompSystemI18n.class.getName(), key); } /** * returns an internationalized string for the given key * @param key the key * @param args the arguments needed to generate the string * @return the internationalized string */ public static String getString(String key, Object[] args) { try { MessageFormat formatter = new MessageFormat(getStringInternal(key)); return formatter.format(args); } catch (MissingResourceException e) { logError(key, e); StringBuffer buf = new StringBuffer(key); for (int i = 0; i < args.length; i++) { if (args[i] != null) { buf.append(" "); //$NON-NLS-1$ buf.append(args[i]); } } return buf.toString(); } } /** * Sets an new language for the I18N. * @param lang a <code>String</code> value. The new language. */ public static void setLanguage(String lang) { Locale.setDefault(new Locale(lang, StringConstants.EMPTY)); } /** * * @return a String representation of the ResourceBundles to use for * fromString(String string) * @see fromString(String string) */ public static String bundlesToString() { final String keyValueSeparator = "="; //$NON-NLS-1$ final String lineBreak = "\n"; //$NON-NLS-1$ final StringBuffer entries = new StringBuffer(); for (Iterator bundlesIt = PLUGIN_BUNDLES.iterator(); bundlesIt.hasNext();) { final ResourceBundle bundle = (ResourceBundle) bundlesIt.next(); for (Enumeration keys = bundle.getKeys(); keys.hasMoreElements();) { final String key = String.valueOf(keys.nextElement()); final String value = bundle.getString(key); entries.append(key).append(keyValueSeparator).append(value).append(lineBreak); } } return entries.toString(); } /** * Creates a ResourceBundle from the given String.<br> * The given String must have the specification of a properties-file:<br> * key=value<br> * key=value<br> * ...<br> * with a line break (\n) after every value. * @param string a String from bundleToString */ public static void fromString(String string) { final ByteArrayInputStream stream = new ByteArrayInputStream(string.getBytes()); try { final PropertyResourceBundle bundle = new PropertyResourceBundle(stream); PLUGIN_BUNDLES.clear(); addResourceBundle(bundle); } catch (IOException e) { log.error(e.getLocalizedMessage(), e); } } }