| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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. |
| */ |
| package org.apache.commons.lang3; |
| |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Collections; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Locale; |
| import java.util.Set; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ConcurrentMap; |
| |
| /** |
| * <p>Operations to assist when working with a {@link Locale}.</p> |
| * |
| * <p>This class tries to handle {@code null} input gracefully. |
| * An exception will not be thrown for a {@code null} input. |
| * Each method documents its behavior in more detail.</p> |
| * |
| * @since 2.2 |
| */ |
| public class LocaleUtils { |
| |
| // class to avoid synchronization (Init on demand) |
| static class SyncAvoid { |
| /** Unmodifiable list of available locales. */ |
| private static final List<Locale> AVAILABLE_LOCALE_LIST; |
| /** Unmodifiable set of available locales. */ |
| private static final Set<Locale> AVAILABLE_LOCALE_SET; |
| |
| static { |
| final List<Locale> list = new ArrayList<>(Arrays.asList(Locale.getAvailableLocales())); // extra safe |
| AVAILABLE_LOCALE_LIST = Collections.unmodifiableList(list); |
| AVAILABLE_LOCALE_SET = Collections.unmodifiableSet(new HashSet<>(list)); |
| } |
| } |
| |
| /** Concurrent map of language locales by country. */ |
| private static final ConcurrentMap<String, List<Locale>> cLanguagesByCountry = |
| new ConcurrentHashMap<>(); |
| |
| /** Concurrent map of country locales by language. */ |
| private static final ConcurrentMap<String, List<Locale>> cCountriesByLanguage = |
| new ConcurrentHashMap<>(); |
| |
| /** |
| * <p>Obtains an unmodifiable list of installed locales.</p> |
| * |
| * <p>This method is a wrapper around {@link Locale#getAvailableLocales()}. |
| * It is more efficient, as the JDK method must create a new array each |
| * time it is called.</p> |
| * |
| * @return the unmodifiable list of available locales |
| */ |
| public static List<Locale> availableLocaleList() { |
| return SyncAvoid.AVAILABLE_LOCALE_LIST; |
| } |
| |
| /** |
| * <p>Obtains an unmodifiable set of installed locales.</p> |
| * |
| * <p>This method is a wrapper around {@link Locale#getAvailableLocales()}. |
| * It is more efficient, as the JDK method must create a new array each |
| * time it is called.</p> |
| * |
| * @return the unmodifiable set of available locales |
| */ |
| public static Set<Locale> availableLocaleSet() { |
| return SyncAvoid.AVAILABLE_LOCALE_SET; |
| } |
| |
| /** |
| * <p>Obtains the list of countries supported for a given language.</p> |
| * |
| * <p>This method takes a language code and searches to find the |
| * countries available for that language. Variant locales are removed.</p> |
| * |
| * @param languageCode the 2 letter language code, null returns empty |
| * @return an unmodifiable List of Locale objects, not null |
| */ |
| public static List<Locale> countriesByLanguage(final String languageCode) { |
| if (languageCode == null) { |
| return Collections.emptyList(); |
| } |
| List<Locale> countries = cCountriesByLanguage.get(languageCode); |
| if (countries == null) { |
| countries = new ArrayList<>(); |
| final List<Locale> locales = availableLocaleList(); |
| for (final Locale locale : locales) { |
| if (languageCode.equals(locale.getLanguage()) && |
| !locale.getCountry().isEmpty() && |
| locale.getVariant().isEmpty()) { |
| countries.add(locale); |
| } |
| } |
| countries = Collections.unmodifiableList(countries); |
| cCountriesByLanguage.putIfAbsent(languageCode, countries); |
| countries = cCountriesByLanguage.get(languageCode); |
| } |
| return countries; |
| } |
| |
| /** |
| * <p>Checks if the locale specified is in the list of available locales.</p> |
| * |
| * @param locale the Locale object to check if it is available |
| * @return true if the locale is a known locale |
| */ |
| public static boolean isAvailableLocale(final Locale locale) { |
| return availableLocaleList().contains(locale); |
| } |
| |
| /** |
| * Checks whether the given String is a ISO 3166 alpha-2 country code. |
| * |
| * @param str the String to check |
| * @return true, is the given String is a ISO 3166 compliant country code. |
| */ |
| private static boolean isISO3166CountryCode(final String str) { |
| return StringUtils.isAllUpperCase(str) && str.length() == 2; |
| } |
| |
| /** |
| * Checks whether the given String is a ISO 639 compliant language code. |
| * |
| * @param str the String to check. |
| * @return true, if the given String is a ISO 639 compliant language code. |
| */ |
| private static boolean isISO639LanguageCode(final String str) { |
| return StringUtils.isAllLowerCase(str) && (str.length() == 2 || str.length() == 3); |
| } |
| |
| /** |
| * Checks whether the given String is a UN M.49 numeric area code. |
| * |
| * @param str the String to check |
| * @return true, is the given String is a UN M.49 numeric area code. |
| */ |
| private static boolean isNumericAreaCode(final String str) { |
| return StringUtils.isNumeric(str) && str.length() == 3; |
| } |
| |
| /** |
| * <p>Obtains the list of languages supported for a given country.</p> |
| * |
| * <p>This method takes a country code and searches to find the |
| * languages available for that country. Variant locales are removed.</p> |
| * |
| * @param countryCode the 2 letter country code, null returns empty |
| * @return an unmodifiable List of Locale objects, not null |
| */ |
| public static List<Locale> languagesByCountry(final String countryCode) { |
| if (countryCode == null) { |
| return Collections.emptyList(); |
| } |
| List<Locale> langs = cLanguagesByCountry.get(countryCode); |
| if (langs == null) { |
| langs = new ArrayList<>(); |
| final List<Locale> locales = availableLocaleList(); |
| for (final Locale locale : locales) { |
| if (countryCode.equals(locale.getCountry()) && |
| locale.getVariant().isEmpty()) { |
| langs.add(locale); |
| } |
| } |
| langs = Collections.unmodifiableList(langs); |
| cLanguagesByCountry.putIfAbsent(countryCode, langs); |
| langs = cLanguagesByCountry.get(countryCode); |
| } |
| return langs; |
| } |
| |
| /** |
| * <p>Obtains the list of locales to search through when performing |
| * a locale search.</p> |
| * |
| * <pre> |
| * localeLookupList(Locale("fr", "CA", "xxx")) |
| * = [Locale("fr", "CA", "xxx"), Locale("fr", "CA"), Locale("fr")] |
| * </pre> |
| * |
| * @param locale the locale to start from |
| * @return the unmodifiable list of Locale objects, 0 being locale, not null |
| */ |
| public static List<Locale> localeLookupList(final Locale locale) { |
| return localeLookupList(locale, locale); |
| } |
| |
| /** |
| * <p>Obtains the list of locales to search through when performing |
| * a locale search.</p> |
| * |
| * <pre> |
| * localeLookupList(Locale("fr", "CA", "xxx"), Locale("en")) |
| * = [Locale("fr", "CA", "xxx"), Locale("fr", "CA"), Locale("fr"), Locale("en"] |
| * </pre> |
| * |
| * <p>The result list begins with the most specific locale, then the |
| * next more general and so on, finishing with the default locale. |
| * The list will never contain the same locale twice.</p> |
| * |
| * @param locale the locale to start from, null returns empty list |
| * @param defaultLocale the default locale to use if no other is found |
| * @return the unmodifiable list of Locale objects, 0 being locale, not null |
| */ |
| public static List<Locale> localeLookupList(final Locale locale, final Locale defaultLocale) { |
| final List<Locale> list = new ArrayList<>(4); |
| if (locale != null) { |
| list.add(locale); |
| if (!locale.getVariant().isEmpty()) { |
| list.add(new Locale(locale.getLanguage(), locale.getCountry())); |
| } |
| if (!locale.getCountry().isEmpty()) { |
| list.add(new Locale(locale.getLanguage(), StringUtils.EMPTY)); |
| } |
| if (!list.contains(defaultLocale)) { |
| list.add(defaultLocale); |
| } |
| } |
| return Collections.unmodifiableList(list); |
| } |
| |
| /** |
| * Tries to parse a locale from the given String. |
| * |
| * @param str the String to parse a locale from. |
| * @return a Locale instance parsed from the given String. |
| * @throws IllegalArgumentException if the given String can not be parsed. |
| */ |
| private static Locale parseLocale(final String str) { |
| if (isISO639LanguageCode(str)) { |
| return new Locale(str); |
| } |
| |
| final String[] segments = str.split("_", -1); |
| final String language = segments[0]; |
| if (segments.length == 2) { |
| final String country = segments[1]; |
| if (isISO639LanguageCode(language) && isISO3166CountryCode(country) || |
| isNumericAreaCode(country)) { |
| return new Locale(language, country); |
| } |
| } else if (segments.length == 3) { |
| final String country = segments[1]; |
| final String variant = segments[2]; |
| if (isISO639LanguageCode(language) && |
| (country.isEmpty() || isISO3166CountryCode(country) || isNumericAreaCode(country)) && |
| !variant.isEmpty()) { |
| return new Locale(language, country, variant); |
| } |
| } |
| throw new IllegalArgumentException("Invalid locale format: " + str); |
| } |
| |
| /** |
| * Returns the given locale if non-{@code null}, otherwise {@link Locale#getDefault()}. |
| * |
| * @param locale a locale or {@code null}. |
| * @return the given locale if non-{@code null}, otherwise {@link Locale#getDefault()}. |
| * @since 3.12.0 |
| */ |
| public static Locale toLocale(final Locale locale) { |
| return locale != null ? locale : Locale.getDefault(); |
| } |
| |
| /** |
| * <p>Converts a String to a Locale.</p> |
| * |
| * <p>This method takes the string format of a locale and creates the |
| * locale object from it.</p> |
| * |
| * <pre> |
| * LocaleUtils.toLocale("") = new Locale("", "") |
| * LocaleUtils.toLocale("en") = new Locale("en", "") |
| * LocaleUtils.toLocale("en_GB") = new Locale("en", "GB") |
| * LocaleUtils.toLocale("en_001") = new Locale("en", "001") |
| * LocaleUtils.toLocale("en_GB_xxx") = new Locale("en", "GB", "xxx") (#) |
| * </pre> |
| * |
| * <p>(#) The behavior of the JDK variant constructor changed between JDK1.3 and JDK1.4. |
| * In JDK1.3, the constructor upper cases the variant, in JDK1.4, it doesn't. |
| * Thus, the result from getVariant() may vary depending on your JDK.</p> |
| * |
| * <p>This method validates the input strictly. |
| * The language code must be lowercase. |
| * The country code must be uppercase. |
| * The separator must be an underscore. |
| * The length must be correct. |
| * </p> |
| * |
| * @param str the locale String to convert, null returns null |
| * @return a Locale, null if null input |
| * @throws IllegalArgumentException if the string is an invalid format |
| * @see Locale#forLanguageTag(String) |
| */ |
| public static Locale toLocale(final String str) { |
| if (str == null) { |
| return null; |
| } |
| if (str.isEmpty()) { // LANG-941 - JDK 8 introduced an empty locale where all fields are blank |
| return new Locale(StringUtils.EMPTY, StringUtils.EMPTY); |
| } |
| if (str.contains("#")) { // LANG-879 - Cannot handle Java 7 script & extensions |
| throw new IllegalArgumentException("Invalid locale format: " + str); |
| } |
| final int len = str.length(); |
| if (len < 2) { |
| throw new IllegalArgumentException("Invalid locale format: " + str); |
| } |
| final char ch0 = str.charAt(0); |
| if (ch0 == '_') { |
| if (len < 3) { |
| throw new IllegalArgumentException("Invalid locale format: " + str); |
| } |
| final char ch1 = str.charAt(1); |
| final char ch2 = str.charAt(2); |
| if (!Character.isUpperCase(ch1) || !Character.isUpperCase(ch2)) { |
| throw new IllegalArgumentException("Invalid locale format: " + str); |
| } |
| if (len == 3) { |
| return new Locale(StringUtils.EMPTY, str.substring(1, 3)); |
| } |
| if (len < 5) { |
| throw new IllegalArgumentException("Invalid locale format: " + str); |
| } |
| if (str.charAt(3) != '_') { |
| throw new IllegalArgumentException("Invalid locale format: " + str); |
| } |
| return new Locale(StringUtils.EMPTY, str.substring(1, 3), str.substring(4)); |
| } |
| |
| return parseLocale(str); |
| } |
| |
| /** |
| * <p>{@code LocaleUtils} instances should NOT be constructed in standard programming. |
| * Instead, the class should be used as {@code LocaleUtils.toLocale("en_GB");}.</p> |
| * |
| * <p>This constructor is public to permit tools that require a JavaBean instance |
| * to operate.</p> |
| */ |
| public LocaleUtils() { |
| } |
| |
| } |