AvailableLanguage.java

/*******************************************************************************
 * Copyright (C) 2015 Connor Lanigan (email: dev@connorlanigan.com)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *******************************************************************************/
package de.norvos.i18n;

import java.util.Arrays;
import java.util.List;
import java.util.Locale;

import de.norvos.utils.Constants;

/**
 * Represents a language that is available in this application.
 *
 * @author Connor Lanigan
 */
public enum AvailableLanguage {
	ENGLISH("English", Locale.ENGLISH),
	GERMAN("Deutsch", Locale.GERMAN),
	SIMPLIFIED_CHINESE("简体中文", Locale.SIMPLIFIED_CHINESE),
	/**
	 * Represents a language used only for testing. Every translated key will be
	 * translated as "XXX", so that it can be seen in the running application
	 * where strings are hardcoded. <strong>Do not use this language in the
	 * production version.</strong>
	 */
	TEST("Test", new Locale("test"));

	/**
	 * Returns an {@link AvailableLanguage} for the given {@link Locale}. Only
	 * the language part of the {@link Locale} is compared, and the region part
	 * is ignored.
	 *
	 * @param locale
	 *            the {@link Locale} for which to get the
	 *            {@link AvailableLanguage}
	 * @return the corresponding {@link AvailableLanguage} or, if no
	 *         corresponding {@link AvailableLanguage} was found,
	 *         <code>null</code>.
	 */
	public static AvailableLanguage forLocaleLanguage(final Locale locale) {
		final String localeLanguage = locale.getLanguage();
		for (final AvailableLanguage language : AvailableLanguage.values()) {
			if (language.getLocale().getLanguage().equals(localeLanguage)) {
				return language;
			}
		}
		return null;
	}

	/**
	 * This returns the language that is probably best suited for a new user. It
	 * uses the systemLocale, if available, or else the Default Language of this
	 * application.
	 */
	public static AvailableLanguage getDefaultLanguage() {
		final Locale systemLocale = Locale.getDefault();
		AvailableLanguage applicationLanguage = forLocaleLanguage(systemLocale);

		if (applicationLanguage == null) {
			applicationLanguage = Constants.DEFAULT_LANGUAGE;
		}

		return applicationLanguage;
	}

	private Locale code;

	private String displayName;

	AvailableLanguage(final String name, final Locale locale) {
		displayName = name;
		code = locale;
	}

	public List<AvailableLanguage> getAll() {
		final List<AvailableLanguage> list = Arrays.asList(values());
		list.remove(AvailableLanguage.TEST);
		return list;
	}

	/**
	 * @return the Locale representing the language
	 */
	public Locale getLocale() {
		return code;
	}

	/**
	 * Returns the name of the language.
	 *
	 * @return the human-readable language name
	 */
	@Override
	public String toString() {
		return displayName;
	}
}