Java tutorial
/* * Copyright 2004 Outerthought bvba and Schaubroeck nv * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* The Apache Software License, Version 1.1 Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved. Redistribution and use in source and binary forms, with or without modifica- tion, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. The end-user documentation included with the redistribution, if any, must include the following acknowledgment: "This product includes software developed by the Apache Software Foundation (http://www.apache.org/)." Alternately, this acknowledgment may appear in the software itself, if and wherever such third-party acknowledgments normally appear. 4. The names "Apache Cocoon" and "Apache Software Foundation" must not be used to endorse or promote products derived from this software without prior written permission. For written permission, please contact apache@apache.org. 5. Products derived from this software may not be called "Apache", nor may "Apache" appear in their name, without prior written permission of the Apache Software Foundation. THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU- DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. This software consists of voluntary contributions made by many individuals on behalf of the Apache Software Foundation and was originally created by Stefano Mazzocchi <stefano@apache.org>. For more information on the Apache Software Foundation, please see <http://www.apache.org/>. */ import java.util.Locale; import java.util.Set; import java.util.StringTokenizer; import java.util.concurrent.ConcurrentHashMap; /** * Map using Locale objects as keys. * * <b>This class is based on code from Apache Cocoon.</b> * * <p>This map should be filled once using calls to {@link #put}, before any calls * are made to {@link #get}. * */ public class LocaleMap { /** Contains the original values the have been put in the map. */ protected ConcurrentHashMap<String, Object> map = new ConcurrentHashMap<String, Object>(); /** Contains 'resolved' locales for quick lookup. */ protected ConcurrentHashMap<String, Object> searchMap = new ConcurrentHashMap<String, Object>(); private static final String NO_RESULT = "(no result: you should never see this)"; /** * Gets an object based on the given locale. An automatic fallback mechanism is used: * if nothing is found for language-COUNTRY-variant, then language-COUNTRY is searched, * the language, and finally "" (empty string). If nothing is found null is returned. */ public Object get(Locale locale) { if (map.size() == 0) return null; String full = getFullKey(locale); if (!searchMap.containsKey(full)) { if (map.containsKey(full)) { Object object = map.get(full); searchMap.put(full, object); return object; } String altKey = locale.getLanguage() + '-' + locale.getCountry(); Object object = map.get(altKey); if (object != null) { searchMap.put(full, object); return object; } altKey = locale.getLanguage(); object = map.get(altKey); if (object != null) { searchMap.put(full, object); return object; } object = map.get(""); if (object != null) { searchMap.put(full, object); return object; } searchMap.put(full, NO_RESULT); } Object result = searchMap.get(full); return result == NO_RESULT ? null : result; } public Object getExact(Locale locale) { return map.get(getString(locale)); } public void clear() { map.clear(); searchMap.clear(); } public void remove(Locale locale) { put(locale, null); } public Locale[] getLocales() { String[] localeNames = map.keySet().toArray(new String[0]); Locale[] locales = new Locale[localeNames.length]; for (int i = 0; i < locales.length; i++) locales[i] = parseLocale(localeNames[i]); return locales; } public Set entrySet() { return map.entrySet(); } private String getFullKey(Locale locale) { return locale.getLanguage() + '-' + locale.getCountry() + '-' + locale.getVariant(); } public void put(Locale locale, Object object) { if (object == null) map.remove(getString(locale)); else map.put(getString(locale), object); searchMap.clear(); } public boolean isEmpty() { return map.isEmpty(); } public boolean equals(Object obj) { if (!(obj instanceof LocaleMap)) return false; LocaleMap other = (LocaleMap) obj; // map can do equals return map.equals(other.map); } public static Locale parseLocale(String localeString) { StringTokenizer localeParser = new StringTokenizer(localeString, "-_"); String lang = null, country = null, variant = null; if (localeParser.hasMoreTokens()) lang = localeParser.nextToken(); if (localeParser.hasMoreTokens()) country = localeParser.nextToken(); if (localeParser.hasMoreTokens()) variant = localeParser.nextToken(); if (lang != null && country != null && variant != null) return new Locale(lang, country, variant); else if (lang != null && country != null) return new Locale(lang, country); else if (lang != null) return new Locale(lang); else return new Locale(""); } public static String getString(Locale locale) { boolean hasLanguage = !locale.getLanguage().equals(""); boolean hasCountry = !locale.getCountry().equals(""); boolean hasVariant = !locale.getVariant().equals(""); if (hasLanguage && hasCountry && hasVariant) return locale.getLanguage() + '-' + locale.getCountry() + '-' + locale.getVariant(); else if (hasLanguage && hasCountry) return locale.getLanguage() + '-' + locale.getCountry(); else if (hasLanguage) return locale.getLanguage(); else return ""; } }