/* * Copyright (c) 1996, 2018, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved * (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved * * The original version of this source code and documentation * is copyrighted and owned by Taligent, Inc., a wholly-owned * subsidiary of IBM. These materials are provided under terms * of a License Agreement between Taligent and Sun. This technology * is protected by multiple US and International patents. * * This notice and attribution to Taligent may not be removed. * Taligent is a registered trademark of Taligent, Inc. * */ package java.util; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.ObjectStreamField; import java.io.Serializable; import java.text.MessageFormat; import java.util.concurrent.ConcurrentHashMap; import java.util.spi.LocaleNameProvider; import java.util.stream.Collectors; import sun.security.action.GetPropertyAction; import sun.util.locale.BaseLocale; import sun.util.locale.InternalLocaleBuilder; import sun.util.locale.LanguageTag; import sun.util.locale.LocaleExtensions; import sun.util.locale.LocaleMatcher; import sun.util.locale.LocaleObjectCache; import sun.util.locale.LocaleSyntaxException; import sun.util.locale.LocaleUtils; import sun.util.locale.ParseStatus; import sun.util.locale.provider.LocaleProviderAdapter; import sun.util.locale.provider.LocaleResources; import sun.util.locale.provider.LocaleServiceProviderPool; import sun.util.locale.provider.TimeZoneNameUtility; /** * A Locale object represents a specific geographical, political, * or cultural region. An operation that requires a Locale to perform * its task is called locale-sensitive and uses the Locale * to tailor information for the user. For example, displaying a number * is a locale-sensitive operation— the number should be formatted * according to the customs and conventions of the user's native country, * region, or culture. * *

The {@code Locale} class implements IETF BCP 47 which is composed of * RFC 4647 "Matching of Language * Tags" and RFC 5646 "Tags * for Identifying Languages" with support for the LDML (UTS#35, "Unicode * Locale Data Markup Language") BCP 47-compatible extensions for locale data * exchange. * *

A Locale object logically consists of the fields * described below. * *

*
language
* *
ISO 639 alpha-2 or alpha-3 language code, or registered * language subtags up to 8 alpha letters (for future enhancements). * When a language has both an alpha-2 code and an alpha-3 code, the * alpha-2 code must be used. You can find a full list of valid * language codes in the IANA Language Subtag Registry (search for * "Type: language"). The language field is case insensitive, but * Locale always canonicalizes to lower case.
* *
Well-formed language values have the form * [a-zA-Z]{2,8}. Note that this is not the full * BCP47 language production, since it excludes extlang. They are * not needed since modern three-letter language codes replace * them.
* *
Example: "en" (English), "ja" (Japanese), "kok" (Konkani)
* *
script
* *
ISO 15924 alpha-4 script code. You can find a full list of * valid script codes in the IANA Language Subtag Registry (search * for "Type: script"). The script field is case insensitive, but * Locale always canonicalizes to title case (the first * letter is upper case and the rest of the letters are lower * case).
* *
Well-formed script values have the form * [a-zA-Z]{4}
* *
Example: "Latn" (Latin), "Cyrl" (Cyrillic)
* *
country (region)
* *
ISO 3166 alpha-2 country code or UN M.49 numeric-3 area code. * You can find a full list of valid country and region codes in the * IANA Language Subtag Registry (search for "Type: region"). The * country (region) field is case insensitive, but * Locale always canonicalizes to upper case.
* *
Well-formed country/region values have * the form [a-zA-Z]{2} | [0-9]{3}
* *
Example: "US" (United States), "FR" (France), "029" * (Caribbean)
* *
variant
* *
Any arbitrary value used to indicate a variation of a * Locale. Where there are two or more variant values * each indicating its own semantics, these values should be ordered * by importance, with most important first, separated by * underscore('_'). The variant field is case sensitive.
* *
Note: IETF BCP 47 places syntactic restrictions on variant * subtags. Also BCP 47 subtags are strictly used to indicate * additional variations that define a language or its dialects that * are not covered by any combinations of language, script and * region subtags. You can find a full list of valid variant codes * in the IANA Language Subtag Registry (search for "Type: variant"). * *

However, the variant field in Locale has * historically been used for any kind of variation, not just * language variations. For example, some supported variants * available in Java SE Runtime Environments indicate alternative * cultural behaviors such as calendar type or number script. In * BCP 47 this kind of information, which does not identify the * language, is supported by extension subtags or private use * subtags.

* *
Well-formed variant values have the form SUBTAG * (('_'|'-') SUBTAG)* where SUBTAG = * [0-9][0-9a-zA-Z]{3} | [0-9a-zA-Z]{5,8}. (Note: BCP 47 only * uses hyphen ('-') as a delimiter, this is more lenient).
* *
Example: "polyton" (Polytonic Greek), "POSIX"
* *
extensions
* *
A map from single character keys to string values, indicating * extensions apart from language identification. The extensions in * Locale implement the semantics and syntax of BCP 47 * extension subtags and private use subtags. The extensions are * case insensitive, but Locale canonicalizes all * extension keys and values to lower case. Note that extensions * cannot have empty values.
* *
Well-formed keys are single characters from the set * [0-9a-zA-Z]. Well-formed values have the form * SUBTAG ('-' SUBTAG)* where for the key 'x' * SUBTAG = [0-9a-zA-Z]{1,8} and for other keys * SUBTAG = [0-9a-zA-Z]{2,8} (that is, 'x' allows * single-character subtags).
* *
Example: key="u"/value="ca-japanese" (Japanese Calendar), * key="x"/value="java-1-7"
*
* * Note: Although BCP 47 requires field values to be registered * in the IANA Language Subtag Registry, the Locale class * does not provide any validation features. The Builder * only checks if an individual field satisfies the syntactic * requirement (is well-formed), but does not validate the value * itself. See {@link Builder} for details. * *

Unicode locale/language extension

* *

UTS#35, "Unicode Locale Data Markup Language" defines optional * attributes and keywords to override or refine the default behavior * associated with a locale. A keyword is represented by a pair of * key and type. For example, "nu-thai" indicates that Thai local * digits (value:"thai") should be used for formatting numbers * (key:"nu"). * *

The keywords are mapped to a BCP 47 extension value using the * extension key 'u' ({@link #UNICODE_LOCALE_EXTENSION}). The above * example, "nu-thai", becomes the extension "u-nu-thai". * *

Thus, when a Locale object contains Unicode locale * attributes and keywords, * getExtension(UNICODE_LOCALE_EXTENSION) will return a * String representing this information, for example, "nu-thai". The * Locale class also provides {@link * #getUnicodeLocaleAttributes}, {@link #getUnicodeLocaleKeys}, and * {@link #getUnicodeLocaleType} which allow you to access Unicode * locale attributes and key/type pairs directly. When represented as * a string, the Unicode Locale Extension lists attributes * alphabetically, followed by key/type sequences with keys listed * alphabetically (the order of subtags comprising a key's type is * fixed when the type is defined) * *

A well-formed locale key has the form * [0-9a-zA-Z]{2}. A well-formed locale type has the * form "" | [0-9a-zA-Z]{3,8} ('-' [0-9a-zA-Z]{3,8})* (it * can be empty, or a series of subtags 3-8 alphanums in length). A * well-formed locale attribute has the form * [0-9a-zA-Z]{3,8} (it is a single subtag with the same * form as a locale type subtag). * *

The Unicode locale extension specifies optional behavior in * locale-sensitive services. Although the LDML specification defines * various keys and values, actual locale-sensitive service * implementations in a Java Runtime Environment might not support any * particular Unicode locale attributes or key/type pairs. * *

Creating a Locale

* *

There are several different ways to create a Locale * object. * *

Builder
* *

Using {@link Builder} you can construct a Locale object * that conforms to BCP 47 syntax. * *

Constructors
* *

The Locale class provides three constructors: *

*
 *     {@link #Locale(String language)}
 *     {@link #Locale(String language, String country)}
 *     {@link #Locale(String language, String country, String variant)}
 * 
*
* These constructors allow you to create a Locale object * with language, country and variant, but you cannot specify * script or extensions. * *
Factory Methods
* *

The method {@link #forLanguageTag} creates a Locale * object for a well-formed BCP 47 language tag. * *

Locale Constants
* *

The Locale class provides a number of convenient constants * that you can use to create Locale objects for commonly used * locales. For example, the following creates a Locale object * for the United States: *

*
 *     Locale.US
 * 
*
* *

Locale Matching

* *

If an application or a system is internationalized and provides localized * resources for multiple locales, it sometimes needs to find one or more * locales (or language tags) which meet each user's specific preferences. Note * that a term "language tag" is used interchangeably with "locale" in this * locale matching documentation. * *

In order to do matching a user's preferred locales to a set of language * tags, RFC 4647 Matching of * Language Tags defines two mechanisms: filtering and lookup. * Filtering is used to get all matching locales, whereas * lookup is to choose the best matching locale. * Matching is done case-insensitively. These matching mechanisms are described * in the following sections. * *

A user's preference is called a Language Priority List and is * expressed as a list of language ranges. There are syntactically two types of * language ranges: basic and extended. See * {@link Locale.LanguageRange Locale.LanguageRange} for details. * *

Filtering
* *

The filtering operation returns all matching language tags. It is defined * in RFC 4647 as follows: * "In filtering, each language range represents the least specific language * tag (that is, the language tag with fewest number of subtags) that is an * acceptable match. All of the language tags in the matching set of tags will * have an equal or greater number of subtags than the language range. Every * non-wildcard subtag in the language range will appear in every one of the * matching language tags." * *

There are two types of filtering: filtering for basic language ranges * (called "basic filtering") and filtering for extended language ranges * (called "extended filtering"). They may return different results by what * kind of language ranges are included in the given Language Priority List. * {@link Locale.FilteringMode} is a parameter to specify how filtering should * be done. * *

Lookup
* *

The lookup operation returns the best matching language tags. It is * defined in RFC 4647 as follows: * "By contrast with filtering, each language range represents the most * specific tag that is an acceptable match. The first matching tag found, * according to the user's priority, is considered the closest match and is the * item returned." * *

For example, if a Language Priority List consists of two language ranges, * {@code "zh-Hant-TW"} and {@code "en-US"}, in prioritized order, lookup * method progressively searches the language tags below in order to find the * best matching language tag. *

*
 *    1. zh-Hant-TW
 *    2. zh-Hant
 *    3. zh
 *    4. en-US
 *    5. en
 * 
*
* If there is a language tag which matches completely to a language range * above, the language tag is returned. * *

{@code "*"} is the special language range, and it is ignored in lookup. * *

If multiple language tags match as a result of the subtag {@code '*'} * included in a language range, the first matching language tag returned by * an {@link Iterator} over a {@link Collection} of language tags is treated as * the best matching one. * *

Use of Locale

* *

Once you've created a Locale you can query it for information * about itself. Use getCountry to get the country (or region) * code and getLanguage to get the language code. * You can use getDisplayCountry to get the * name of the country suitable for displaying to the user. Similarly, * you can use getDisplayLanguage to get the name of * the language suitable for displaying to the user. Interestingly, * the getDisplayXXX methods are themselves locale-sensitive * and have two versions: one that uses the default * {@link Locale.Category#DISPLAY DISPLAY} locale and one * that uses the locale specified as an argument. * *

The Java Platform provides a number of classes that perform locale-sensitive * operations. For example, the NumberFormat class formats * numbers, currency, and percentages in a locale-sensitive manner. Classes * such as NumberFormat have several convenience methods * for creating a default object of that type. For example, the * NumberFormat class provides these three convenience methods * for creating a default NumberFormat object: *

*
 *     NumberFormat.getInstance()
 *     NumberFormat.getCurrencyInstance()
 *     NumberFormat.getPercentInstance()
 * 
*
* Each of these methods has two variants; one with an explicit locale * and one without; the latter uses the default * {@link Locale.Category#FORMAT FORMAT} locale: *
*
 *     NumberFormat.getInstance(myLocale)
 *     NumberFormat.getCurrencyInstance(myLocale)
 *     NumberFormat.getPercentInstance(myLocale)
 * 
*
* A Locale is the mechanism for identifying the kind of object * (NumberFormat) that you would like to get. The locale is * just a mechanism for identifying objects, * not a container for the objects themselves. * *

Compatibility

* *

In order to maintain compatibility with existing usage, Locale's * constructors retain their behavior prior to the Java Runtime * Environment version 1.7. The same is largely true for the * toString method. Thus Locale objects can continue to * be used as they were. In particular, clients who parse the output * of toString into language, country, and variant fields can continue * to do so (although this is strongly discouraged), although the * variant field will have additional information in it if script or * extensions are present. * *

In addition, BCP 47 imposes syntax restrictions that are not * imposed by Locale's constructors. This means that conversions * between some Locales and BCP 47 language tags cannot be made without * losing information. Thus toLanguageTag cannot * represent the state of locales whose language, country, or variant * do not conform to BCP 47. * *

Because of these issues, it is recommended that clients migrate * away from constructing non-conforming locales and use the * forLanguageTag and Locale.Builder APIs instead. * Clients desiring a string representation of the complete locale can * then always rely on toLanguageTag for this purpose. * *

Special cases
* *

For compatibility reasons, two * non-conforming locales are treated as special cases. These are * {@code ja_JP_JP} and {@code th_TH_TH}. These are ill-formed * in BCP 47 since the variants are too short. To ease migration to BCP 47, * these are treated specially during construction. These two cases (and only * these) cause a constructor to generate an extension, all other values behave * exactly as they did prior to Java 7. * *

Java has used {@code ja_JP_JP} to represent Japanese as used in * Japan together with the Japanese Imperial calendar. This is now * representable using a Unicode locale extension, by specifying the * Unicode locale key {@code ca} (for "calendar") and type * {@code japanese}. When the Locale constructor is called with the * arguments "ja", "JP", "JP", the extension "u-ca-japanese" is * automatically added. * *

Java has used {@code th_TH_TH} to represent Thai as used in * Thailand together with Thai digits. This is also now representable using * a Unicode locale extension, by specifying the Unicode locale key * {@code nu} (for "number") and value {@code thai}. When the Locale * constructor is called with the arguments "th", "TH", "TH", the * extension "u-nu-thai" is automatically added. * *

Serialization
* *

During serialization, writeObject writes all fields to the output * stream, including extensions. * *

During deserialization, readResolve adds extensions as described * in Special Cases, only * for the two cases th_TH_TH and ja_JP_JP. * *

Legacy language codes
* *

Locale's constructor has always converted three language codes to * their earlier, obsoleted forms: {@code he} maps to {@code iw}, * {@code yi} maps to {@code ji}, and {@code id} maps to * {@code in}. This continues to be the case, in order to not break * backwards compatibility. * *

The APIs added in 1.7 map between the old and new language codes, * maintaining the old codes internal to Locale (so that * getLanguage and toString reflect the old * code), but using the new codes in the BCP 47 language tag APIs (so * that toLanguageTag reflects the new one). This * preserves the equivalence between Locales no matter which code or * API is used to construct them. Java's default resource bundle * lookup mechanism also implements this mapping, so that resources * can be named using either convention, see {@link ResourceBundle.Control}. * *

Three-letter language/country(region) codes
* *

The Locale constructors have always specified that the language * and the country param be two characters in length, although in * practice they have accepted any length. The specification has now * been relaxed to allow language codes of two to eight characters and * country (region) codes of two to three characters, and in * particular, three-letter language codes and three-digit region * codes as specified in the IANA Language Subtag Registry. For * compatibility, the implementation still does not impose a length * constraint. * * @see Builder * @see ResourceBundle * @see java.text.Format * @see java.text.NumberFormat * @see java.text.Collator * @author Mark Davis * @since 1.1 */ public final class Locale implements Cloneable, Serializable { private static final Cache LOCALECACHE = new Cache(); /** Useful constant for language. */ public static final Locale ENGLISH = createConstant("en", ""); /** Useful constant for language. */ public static final Locale FRENCH = createConstant("fr", ""); /** Useful constant for language. */ public static final Locale GERMAN = createConstant("de", ""); /** Useful constant for language. */ public static final Locale ITALIAN = createConstant("it", ""); /** Useful constant for language. */ public static final Locale JAPANESE = createConstant("ja", ""); /** Useful constant for language. */ public static final Locale KOREAN = createConstant("ko", ""); /** Useful constant for language. */ public static final Locale CHINESE = createConstant("zh", ""); /** Useful constant for language. */ public static final Locale SIMPLIFIED_CHINESE = createConstant("zh", "CN"); /** Useful constant for language. */ public static final Locale TRADITIONAL_CHINESE = createConstant("zh", "TW"); /** Useful constant for country. */ public static final Locale FRANCE = createConstant("fr", "FR"); /** Useful constant for country. */ public static final Locale GERMANY = createConstant("de", "DE"); /** Useful constant for country. */ public static final Locale ITALY = createConstant("it", "IT"); /** Useful constant for country. */ public static final Locale JAPAN = createConstant("ja", "JP"); /** Useful constant for country. */ public static final Locale KOREA = createConstant("ko", "KR"); /** Useful constant for country. */ public static final Locale CHINA = SIMPLIFIED_CHINESE; /** Useful constant for country. */ public static final Locale PRC = SIMPLIFIED_CHINESE; /** Useful constant for country. */ public static final Locale TAIWAN = TRADITIONAL_CHINESE; /** Useful constant for country. */ public static final Locale UK = createConstant("en", "GB"); /** Useful constant for country. */ public static final Locale US = createConstant("en", "US"); /** Useful constant for country. */ public static final Locale CANADA = createConstant("en", "CA"); /** Useful constant for country. */ public static final Locale CANADA_FRENCH = createConstant("fr", "CA"); /** * Useful constant for the root locale. The root locale is the locale whose * language, country, and variant are empty ("") strings. This is regarded * as the base locale of all locales, and is used as the language/country * neutral locale for the locale sensitive operations. * * @since 1.6 */ public static final Locale ROOT = createConstant("", ""); /** * The key for the private use extension ('x'). * * @see #getExtension(char) * @see Builder#setExtension(char, String) * @since 1.7 */ public static final char PRIVATE_USE_EXTENSION = 'x'; /** * The key for Unicode locale extension ('u'). * * @see #getExtension(char) * @see Builder#setExtension(char, String) * @since 1.7 */ public static final char UNICODE_LOCALE_EXTENSION = 'u'; /** serialization ID */ static final long serialVersionUID = 9149081749638150636L; /** * Enum for specifying the type defined in ISO 3166. This enum is used to * retrieve the two-letter ISO3166-1 alpha-2, three-letter ISO3166-1 * alpha-3, four-letter ISO3166-3 country codes. * * @see #getISOCountries(Locale.IsoCountryCode) * @since 9 */ public static enum IsoCountryCode { /** * PART1_ALPHA2 is used to represent the ISO3166-1 alpha-2 two letter * country codes. */ PART1_ALPHA2 { @Override Set createCountryCodeSet() { return Set.of(Locale.getISOCountries()); } }, /** * * PART1_ALPHA3 is used to represent the ISO3166-1 alpha-3 three letter * country codes. */ PART1_ALPHA3 { @Override Set createCountryCodeSet() { return LocaleISOData.computeISO3166_1Alpha3Countries(); } }, /** * PART3 is used to represent the ISO3166-3 four letter country codes. */ PART3 { @Override Set createCountryCodeSet() { return Set.of(LocaleISOData.ISO3166_3); } }; /** * Concrete implementation of this method attempts to compute value * for iso3166CodesMap for each IsoCountryCode type key. */ abstract Set createCountryCodeSet(); /** * Map to hold country codes for each ISO3166 part. */ private static Map> iso3166CodesMap = new ConcurrentHashMap<>(); /** * This method is called from Locale class to retrieve country code set * for getISOCountries(type) */ static Set retrieveISOCountryCodes(IsoCountryCode type) { return iso3166CodesMap.computeIfAbsent(type, IsoCountryCode::createCountryCodeSet); } } /** * Display types for retrieving localized names from the name providers. */ private static final int DISPLAY_LANGUAGE = 0; private static final int DISPLAY_COUNTRY = 1; private static final int DISPLAY_VARIANT = 2; private static final int DISPLAY_SCRIPT = 3; private static final int DISPLAY_UEXT_KEY = 4; private static final int DISPLAY_UEXT_TYPE = 5; /** * Private constructor used by getInstance method */ private Locale(BaseLocale baseLocale, LocaleExtensions extensions) { this.baseLocale = baseLocale; this.localeExtensions = extensions; } /** * Construct a locale from language, country and variant. * This constructor normalizes the language value to lowercase and * the country value to uppercase. *

* Note: *

* * @param language An ISO 639 alpha-2 or alpha-3 language code, or a language subtag * up to 8 characters in length. See the Locale class description about * valid language values. * @param country An ISO 3166 alpha-2 country code or a UN M.49 numeric-3 area code. * See the Locale class description about valid country values. * @param variant Any arbitrary value used to indicate a variation of a Locale. * See the Locale class description for the details. * @exception NullPointerException thrown if any argument is null. */ public Locale(String language, String country, String variant) { if (language== null || country == null || variant == null) { throw new NullPointerException(); } baseLocale = BaseLocale.getInstance(convertOldISOCodes(language), "", country, variant); localeExtensions = getCompatibilityExtensions(language, "", country, variant); } /** * Construct a locale from language and country. * This constructor normalizes the language value to lowercase and * the country value to uppercase. *

* Note: *

* * @param language An ISO 639 alpha-2 or alpha-3 language code, or a language subtag * up to 8 characters in length. See the Locale class description about * valid language values. * @param country An ISO 3166 alpha-2 country code or a UN M.49 numeric-3 area code. * See the Locale class description about valid country values. * @exception NullPointerException thrown if either argument is null. */ public Locale(String language, String country) { this(language, country, ""); } /** * Construct a locale from a language code. * This constructor normalizes the language value to lowercase. *

* Note: *

* * @param language An ISO 639 alpha-2 or alpha-3 language code, or a language subtag * up to 8 characters in length. See the Locale class description about * valid language values. * @exception NullPointerException thrown if argument is null. * @since 1.4 */ public Locale(String language) { this(language, "", ""); } /** * This method must be called only for creating the Locale.* * constants due to making shortcuts. */ private static Locale createConstant(String lang, String country) { BaseLocale base = BaseLocale.createInstance(lang, country); return getInstance(base, null); } /** * Returns a Locale constructed from the given * language, country and * variant. If the same Locale instance * is available in the cache, then that instance is * returned. Otherwise, a new Locale instance is * created and cached. * * @param language lowercase 2 to 8 language code. * @param country uppercase two-letter ISO-3166 code and numeric-3 UN M.49 area code. * @param variant vendor and browser specific code. See class description. * @return the Locale instance requested * @exception NullPointerException if any argument is null. */ static Locale getInstance(String language, String country, String variant) { return getInstance(language, "", country, variant, null); } static Locale getInstance(String language, String script, String country, String variant, LocaleExtensions extensions) { if (language== null || script == null || country == null || variant == null) { throw new NullPointerException(); } if (extensions == null) { extensions = getCompatibilityExtensions(language, script, country, variant); } BaseLocale baseloc = BaseLocale.getInstance(language, script, country, variant); return getInstance(baseloc, extensions); } static Locale getInstance(BaseLocale baseloc, LocaleExtensions extensions) { if (extensions == null) { return LOCALECACHE.get(baseloc); } else { LocaleKey key = new LocaleKey(baseloc, extensions); return LOCALECACHE.get(key); } } private static class Cache extends LocaleObjectCache { private Cache() { } @Override protected Locale createObject(Object key) { if (key instanceof BaseLocale) { return new Locale((BaseLocale)key, null); } else { LocaleKey lk = (LocaleKey)key; return new Locale(lk.base, lk.exts); } } } private static final class LocaleKey { private final BaseLocale base; private final LocaleExtensions exts; private final int hash; private LocaleKey(BaseLocale baseLocale, LocaleExtensions extensions) { base = baseLocale; exts = extensions; // Calculate the hash value here because it's always used. int h = base.hashCode(); if (exts != null) { h ^= exts.hashCode(); } hash = h; } @Override public boolean equals(Object obj) { if (this == obj) { return true; } if (!(obj instanceof LocaleKey)) { return false; } LocaleKey other = (LocaleKey)obj; if (hash != other.hash || !base.equals(other.base)) { return false; } if (exts == null) { return other.exts == null; } return exts.equals(other.exts); } @Override public int hashCode() { return hash; } } /** * Gets the current value of the default locale for this instance * of the Java Virtual Machine. *

* The Java Virtual Machine sets the default locale during startup * based on the host environment. It is used by many locale-sensitive * methods if no locale is explicitly specified. * It can be changed using the * {@link #setDefault(java.util.Locale) setDefault} method. * * @return the default locale for this instance of the Java Virtual Machine */ public static Locale getDefault() { // do not synchronize this method - see 4071298 return defaultLocale; } /** * Gets the current value of the default locale for the specified Category * for this instance of the Java Virtual Machine. *

* The Java Virtual Machine sets the default locale during startup based * on the host environment. It is used by many locale-sensitive methods * if no locale is explicitly specified. It can be changed using the * setDefault(Locale.Category, Locale) method. * * @param category - the specified category to get the default locale * @throws NullPointerException if category is null * @return the default locale for the specified Category for this instance * of the Java Virtual Machine * @see #setDefault(Locale.Category, Locale) * @since 1.7 */ public static Locale getDefault(Locale.Category category) { // do not synchronize this method - see 4071298 switch (category) { case DISPLAY: if (defaultDisplayLocale == null) { synchronized(Locale.class) { if (defaultDisplayLocale == null) { defaultDisplayLocale = initDefault(category); } } } return defaultDisplayLocale; case FORMAT: if (defaultFormatLocale == null) { synchronized(Locale.class) { if (defaultFormatLocale == null) { defaultFormatLocale = initDefault(category); } } } return defaultFormatLocale; default: assert false: "Unknown Category"; } return getDefault(); } private static Locale initDefault() { String language, region, script, country, variant; Properties props = GetPropertyAction.privilegedGetProperties(); language = props.getProperty("user.language", "en"); // for compatibility, check for old user.region property region = props.getProperty("user.region"); if (region != null) { // region can be of form country, country_variant, or _variant int i = region.indexOf('_'); if (i >= 0) { country = region.substring(0, i); variant = region.substring(i + 1); } else { country = region; variant = ""; } script = ""; } else { script = props.getProperty("user.script", ""); country = props.getProperty("user.country", ""); variant = props.getProperty("user.variant", ""); } return getInstance(language, script, country, variant, getDefaultExtensions(props.getProperty("user.extensions", "")) .orElse(null)); } private static Locale initDefault(Locale.Category category) { Properties props = GetPropertyAction.privilegedGetProperties(); return getInstance( props.getProperty(category.languageKey, defaultLocale.getLanguage()), props.getProperty(category.scriptKey, defaultLocale.getScript()), props.getProperty(category.countryKey, defaultLocale.getCountry()), props.getProperty(category.variantKey, defaultLocale.getVariant()), getDefaultExtensions(props.getProperty(category.extensionsKey, "")) .orElse(defaultLocale.getLocaleExtensions())); } private static Optional getDefaultExtensions(String extensionsProp) { LocaleExtensions exts = null; try { exts = new InternalLocaleBuilder() .setExtensions(extensionsProp) .getLocaleExtensions(); } catch (LocaleSyntaxException e) { // just ignore this incorrect property } return Optional.ofNullable(exts); } /** * Sets the default locale for this instance of the Java Virtual Machine. * This does not affect the host locale. *

* If there is a security manager, its checkPermission * method is called with a PropertyPermission("user.language", "write") * permission before the default locale is changed. *

* The Java Virtual Machine sets the default locale during startup * based on the host environment. It is used by many locale-sensitive * methods if no locale is explicitly specified. *

* Since changing the default locale may affect many different areas * of functionality, this method should only be used if the caller * is prepared to reinitialize locale-sensitive code running * within the same Java Virtual Machine. *

* By setting the default locale with this method, all of the default * locales for each Category are also set to the specified default locale. * * @throws SecurityException * if a security manager exists and its * checkPermission method doesn't allow the operation. * @throws NullPointerException if newLocale is null * @param newLocale the new default locale * @see SecurityManager#checkPermission * @see java.util.PropertyPermission */ public static synchronized void setDefault(Locale newLocale) { setDefault(Category.DISPLAY, newLocale); setDefault(Category.FORMAT, newLocale); defaultLocale = newLocale; } /** * Sets the default locale for the specified Category for this instance * of the Java Virtual Machine. This does not affect the host locale. *

* If there is a security manager, its checkPermission method is called * with a PropertyPermission("user.language", "write") permission before * the default locale is changed. *

* The Java Virtual Machine sets the default locale during startup based * on the host environment. It is used by many locale-sensitive methods * if no locale is explicitly specified. *

* Since changing the default locale may affect many different areas of * functionality, this method should only be used if the caller is * prepared to reinitialize locale-sensitive code running within the * same Java Virtual Machine. * * @param category - the specified category to set the default locale * @param newLocale - the new default locale * @throws SecurityException if a security manager exists and its * checkPermission method doesn't allow the operation. * @throws NullPointerException if category and/or newLocale is null * @see SecurityManager#checkPermission(java.security.Permission) * @see PropertyPermission * @see #getDefault(Locale.Category) * @since 1.7 */ public static synchronized void setDefault(Locale.Category category, Locale newLocale) { if (category == null) throw new NullPointerException("Category cannot be NULL"); if (newLocale == null) throw new NullPointerException("Can't set default locale to NULL"); SecurityManager sm = System.getSecurityManager(); if (sm != null) sm.checkPermission(new PropertyPermission ("user.language", "write")); switch (category) { case DISPLAY: defaultDisplayLocale = newLocale; break; case FORMAT: defaultFormatLocale = newLocale; break; default: assert false: "Unknown Category"; } } /** * Returns an array of all installed locales. * The returned array represents the union of locales supported * by the Java runtime environment and by installed * {@link java.util.spi.LocaleServiceProvider LocaleServiceProvider} * implementations. It must contain at least a Locale * instance equal to {@link java.util.Locale#US Locale.US}. * * @return An array of installed locales. */ public static Locale[] getAvailableLocales() { return LocaleServiceProviderPool.getAllAvailableLocales(); } /** * Returns a list of all 2-letter country codes defined in ISO 3166. * Can be used to create Locales. * This method is equivalent to {@link #getISOCountries(Locale.IsoCountryCode type)} * with {@code type} {@link IsoCountryCode#PART1_ALPHA2}. *

* Note: The Locale class also supports other codes for * country (region), such as 3-letter numeric UN M.49 area codes. * Therefore, the list returned by this method does not contain ALL valid * codes that can be used to create Locales. *

* Note that this method does not return obsolete 2-letter country codes. * ISO3166-3 codes which designate country codes for those obsolete codes, * can be retrieved from {@link #getISOCountries(Locale.IsoCountryCode type)} with * {@code type} {@link IsoCountryCode#PART3}. * @return An array of ISO 3166 two-letter country codes. */ public static String[] getISOCountries() { if (isoCountries == null) { isoCountries = getISO2Table(LocaleISOData.isoCountryTable); } String[] result = new String[isoCountries.length]; System.arraycopy(isoCountries, 0, result, 0, isoCountries.length); return result; } /** * Returns a {@code Set} of ISO3166 country codes for the specified type. * * @param type {@link Locale.IsoCountryCode} specified ISO code type. * @see java.util.Locale.IsoCountryCode * @throws NullPointerException if type is null * @return a {@code Set} of ISO country codes for the specified type. * @since 9 */ public static Set getISOCountries(IsoCountryCode type) { Objects.requireNonNull(type); return IsoCountryCode.retrieveISOCountryCodes(type); } /** * Returns a list of all 2-letter language codes defined in ISO 639. * Can be used to create Locales. *

* Note: *

* * @return An array of ISO 639 two-letter language codes. */ public static String[] getISOLanguages() { if (isoLanguages == null) { isoLanguages = getISO2Table(LocaleISOData.isoLanguageTable); } String[] result = new String[isoLanguages.length]; System.arraycopy(isoLanguages, 0, result, 0, isoLanguages.length); return result; } private static String[] getISO2Table(String table) { int len = table.length() / 5; String[] isoTable = new String[len]; for (int i = 0, j = 0; i < len; i++, j += 5) { isoTable[i] = table.substring(j, j + 2); } return isoTable; } /** * Returns the language code of this Locale. * *

Note: ISO 639 is not a stable standard— some languages' codes have changed. * Locale's constructor recognizes both the new and the old codes for the languages * whose codes have changed, but this function always returns the old code. If you * want to check for a specific language whose code has changed, don't do *

     * if (locale.getLanguage().equals("he")) // BAD!
     *    ...
     * 
* Instead, do *
     * if (locale.getLanguage().equals(new Locale("he").getLanguage()))
     *    ...
     * 
* @return The language code, or the empty string if none is defined. * @see #getDisplayLanguage */ public String getLanguage() { return baseLocale.getLanguage(); } /** * Returns the script for this locale, which should * either be the empty string or an ISO 15924 4-letter script * code. The first letter is uppercase and the rest are * lowercase, for example, 'Latn', 'Cyrl'. * * @return The script code, or the empty string if none is defined. * @see #getDisplayScript * @since 1.7 */ public String getScript() { return baseLocale.getScript(); } /** * Returns the country/region code for this locale, which should * either be the empty string, an uppercase ISO 3166 2-letter code, * or a UN M.49 3-digit code. * * @return The country/region code, or the empty string if none is defined. * @see #getDisplayCountry */ public String getCountry() { return baseLocale.getRegion(); } /** * Returns the variant code for this locale. * * @return The variant code, or the empty string if none is defined. * @see #getDisplayVariant */ public String getVariant() { return baseLocale.getVariant(); } /** * Returns {@code true} if this {@code Locale} has any * extensions. * * @return {@code true} if this {@code Locale} has any extensions * @since 1.8 */ public boolean hasExtensions() { return localeExtensions != null; } /** * Returns a copy of this {@code Locale} with no * extensions. If this {@code Locale} has no extensions, this {@code Locale} * is returned. * * @return a copy of this {@code Locale} with no extensions, or {@code this} * if {@code this} has no extensions * @since 1.8 */ public Locale stripExtensions() { return hasExtensions() ? Locale.getInstance(baseLocale, null) : this; } /** * Returns the extension (or private use) value associated with * the specified key, or null if there is no extension * associated with the key. To be well-formed, the key must be one * of [0-9A-Za-z]. Keys are case-insensitive, so * for example 'z' and 'Z' represent the same extension. * * @param key the extension key * @return The extension, or null if this locale defines no * extension for the specified key. * @throws IllegalArgumentException if key is not well-formed * @see #PRIVATE_USE_EXTENSION * @see #UNICODE_LOCALE_EXTENSION * @since 1.7 */ public String getExtension(char key) { if (!LocaleExtensions.isValidKey(key)) { throw new IllegalArgumentException("Ill-formed extension key: " + key); } return hasExtensions() ? localeExtensions.getExtensionValue(key) : null; } /** * Returns the set of extension keys associated with this locale, or the * empty set if it has no extensions. The returned set is unmodifiable. * The keys will all be lower-case. * * @return The set of extension keys, or the empty set if this locale has * no extensions. * @since 1.7 */ public Set getExtensionKeys() { if (!hasExtensions()) { return Collections.emptySet(); } return localeExtensions.getKeys(); } /** * Returns the set of unicode locale attributes associated with * this locale, or the empty set if it has no attributes. The * returned set is unmodifiable. * * @return The set of attributes. * @since 1.7 */ public Set getUnicodeLocaleAttributes() { if (!hasExtensions()) { return Collections.emptySet(); } return localeExtensions.getUnicodeLocaleAttributes(); } /** * Returns the Unicode locale type associated with the specified Unicode locale key * for this locale. Returns the empty string for keys that are defined with no type. * Returns null if the key is not defined. Keys are case-insensitive. The key must * be two alphanumeric characters ([0-9a-zA-Z]), or an IllegalArgumentException is * thrown. * * @param key the Unicode locale key * @return The Unicode locale type associated with the key, or null if the * locale does not define the key. * @throws IllegalArgumentException if the key is not well-formed * @throws NullPointerException if key is null * @since 1.7 */ public String getUnicodeLocaleType(String key) { if (!isUnicodeExtensionKey(key)) { throw new IllegalArgumentException("Ill-formed Unicode locale key: " + key); } return hasExtensions() ? localeExtensions.getUnicodeLocaleType(key) : null; } /** * Returns the set of Unicode locale keys defined by this locale, or the empty set if * this locale has none. The returned set is immutable. Keys are all lower case. * * @return The set of Unicode locale keys, or the empty set if this locale has * no Unicode locale keywords. * @since 1.7 */ public Set getUnicodeLocaleKeys() { if (localeExtensions == null) { return Collections.emptySet(); } return localeExtensions.getUnicodeLocaleKeys(); } /** * Package locale method returning the Locale's BaseLocale, * used by ResourceBundle * @return base locale of this Locale */ BaseLocale getBaseLocale() { return baseLocale; } /** * Package private method returning the Locale's LocaleExtensions, * used by ResourceBundle. * @return locale extensions of this Locale, * or {@code null} if no extensions are defined */ LocaleExtensions getLocaleExtensions() { return localeExtensions; } /** * Returns a string representation of this Locale * object, consisting of language, country, variant, script, * and extensions as below: *
* language + "_" + country + "_" + (variant + "_#" | "#") + script + "_" + extensions *
* * Language is always lower case, country is always upper case, script is always title * case, and extensions are always lower case. Extensions and private use subtags * will be in canonical order as explained in {@link #toLanguageTag}. * *

When the locale has neither script nor extensions, the result is the same as in * Java 6 and prior. * *

If both the language and country fields are missing, this function will return * the empty string, even if the variant, script, or extensions field is present (you * can't have a locale with just a variant, the variant must accompany a well-formed * language or country code). * *

If script or extensions are present and variant is missing, no underscore is * added before the "#". * *

This behavior is designed to support debugging and to be compatible with * previous uses of toString that expected language, country, and variant * fields only. To represent a Locale as a String for interchange purposes, use * {@link #toLanguageTag}. * *

Examples:

    *
  • {@code en}
  • *
  • {@code de_DE}
  • *
  • {@code _GB}
  • *
  • {@code en_US_WIN}
  • *
  • {@code de__POSIX}
  • *
  • {@code zh_CN_#Hans}
  • *
  • {@code zh_TW_#Hant_x-java}
  • *
  • {@code th_TH_TH_#u-nu-thai}
* * @return A string representation of the Locale, for debugging. * @see #getDisplayName * @see #toLanguageTag */ @Override public final String toString() { boolean l = (baseLocale.getLanguage().length() != 0); boolean s = (baseLocale.getScript().length() != 0); boolean r = (baseLocale.getRegion().length() != 0); boolean v = (baseLocale.getVariant().length() != 0); boolean e = (localeExtensions != null && localeExtensions.getID().length() != 0); StringBuilder result = new StringBuilder(baseLocale.getLanguage()); if (r || (l && (v || s || e))) { result.append('_') .append(baseLocale.getRegion()); // This may just append '_' } if (v && (l || r)) { result.append('_') .append(baseLocale.getVariant()); } if (s && (l || r)) { result.append("_#") .append(baseLocale.getScript()); } if (e && (l || r)) { result.append('_'); if (!s) { result.append('#'); } result.append(localeExtensions.getID()); } return result.toString(); } /** * Returns a well-formed IETF BCP 47 language tag representing * this locale. * *

If this Locale has a language, country, or * variant that does not satisfy the IETF BCP 47 language tag * syntax requirements, this method handles these fields as * described below: * *

Language: If language is empty, or not well-formed (for example "a" or * "e2"), it will be emitted as "und" (Undetermined). * *

Country: If country is not well-formed (for example "12" or "USA"), * it will be omitted. * *

Variant: If variant is well-formed, each sub-segment * (delimited by '-' or '_') is emitted as a subtag. Otherwise: *

    * *
  • if all sub-segments match [0-9a-zA-Z]{1,8} * (for example "WIN" or "Oracle_JDK_Standard_Edition"), the first * ill-formed sub-segment and all following will be appended to * the private use subtag. The first appended subtag will be * "lvariant", followed by the sub-segments in order, separated by * hyphen. For example, "x-lvariant-WIN", * "Oracle-x-lvariant-JDK-Standard-Edition". * *
  • if any sub-segment does not match * [0-9a-zA-Z]{1,8}, the variant will be truncated * and the problematic sub-segment and all following sub-segments * will be omitted. If the remainder is non-empty, it will be * emitted as a private use subtag as above (even if the remainder * turns out to be well-formed). For example, * "Solaris_isjustthecoolestthing" is emitted as * "x-lvariant-Solaris", not as "solaris".
* *

Special Conversions: Java supports some old locale * representations, including deprecated ISO language codes, * for compatibility. This method performs the following * conversions: *

    * *
  • Deprecated ISO language codes "iw", "ji", and "in" are * converted to "he", "yi", and "id", respectively. * *
  • A locale with language "no", country "NO", and variant * "NY", representing Norwegian Nynorsk (Norway), is converted * to a language tag "nn-NO".
* *

Note: Although the language tag created by this * method is well-formed (satisfies the syntax requirements * defined by the IETF BCP 47 specification), it is not * necessarily a valid BCP 47 language tag. For example, *

     *   new Locale("xx", "YY").toLanguageTag();
* * will return "xx-YY", but the language subtag "xx" and the * region subtag "YY" are invalid because they are not registered * in the IANA Language Subtag Registry. * * @return a BCP47 language tag representing the locale * @see #forLanguageTag(String) * @since 1.7 */ public String toLanguageTag() { if (languageTag != null) { return languageTag; } LanguageTag tag = LanguageTag.parseLocale(baseLocale, localeExtensions); StringBuilder buf = new StringBuilder(); String subtag = tag.getLanguage(); if (subtag.length() > 0) { buf.append(LanguageTag.canonicalizeLanguage(subtag)); } subtag = tag.getScript(); if (subtag.length() > 0) { buf.append(LanguageTag.SEP); buf.append(LanguageTag.canonicalizeScript(subtag)); } subtag = tag.getRegion(); if (subtag.length() > 0) { buf.append(LanguageTag.SEP); buf.append(LanguageTag.canonicalizeRegion(subtag)); } Listsubtags = tag.getVariants(); for (String s : subtags) { buf.append(LanguageTag.SEP); // preserve casing buf.append(s); } subtags = tag.getExtensions(); for (String s : subtags) { buf.append(LanguageTag.SEP); buf.append(LanguageTag.canonicalizeExtension(s)); } subtag = tag.getPrivateuse(); if (subtag.length() > 0) { if (buf.length() > 0) { buf.append(LanguageTag.SEP); } buf.append(LanguageTag.PRIVATEUSE).append(LanguageTag.SEP); // preserve casing buf.append(subtag); } String langTag = buf.toString(); synchronized (this) { if (languageTag == null) { languageTag = langTag; } } return languageTag; } /** * Returns a locale for the specified IETF BCP 47 language tag string. * *

If the specified language tag contains any ill-formed subtags, * the first such subtag and all following subtags are ignored. Compare * to {@link Locale.Builder#setLanguageTag} which throws an exception * in this case. * *

The following conversions are performed:

    * *
  • The language code "und" is mapped to language "". * *
  • The language codes "he", "yi", and "id" are mapped to "iw", * "ji", and "in" respectively. (This is the same canonicalization * that's done in Locale's constructors.) * *
  • The portion of a private use subtag prefixed by "lvariant", * if any, is removed and appended to the variant field in the * result locale (without case normalization). If it is then * empty, the private use subtag is discarded: * *
         *     Locale loc;
         *     loc = Locale.forLanguageTag("en-US-x-lvariant-POSIX");
         *     loc.getVariant(); // returns "POSIX"
         *     loc.getExtension('x'); // returns null
         *
         *     loc = Locale.forLanguageTag("de-POSIX-x-URP-lvariant-Abc-Def");
         *     loc.getVariant(); // returns "POSIX_Abc_Def"
         *     loc.getExtension('x'); // returns "urp"
         * 
    * *
  • When the languageTag argument contains an extlang subtag, * the first such subtag is used as the language, and the primary * language subtag and other extlang subtags are ignored: * *
         *     Locale.forLanguageTag("ar-aao").getLanguage(); // returns "aao"
         *     Locale.forLanguageTag("en-abc-def-us").toString(); // returns "abc_US"
         * 
    * *
  • Case is normalized except for variant tags, which are left * unchanged. Language is normalized to lower case, script to * title case, country to upper case, and extensions to lower * case. * *
  • If, after processing, the locale would exactly match either * ja_JP_JP or th_TH_TH with no extensions, the appropriate * extensions are added as though the constructor had been called: * *
         *    Locale.forLanguageTag("ja-JP-x-lvariant-JP").toLanguageTag();
         *    // returns "ja-JP-u-ca-japanese-x-lvariant-JP"
         *    Locale.forLanguageTag("th-TH-x-lvariant-TH").toLanguageTag();
         *    // returns "th-TH-u-nu-thai-x-lvariant-TH"
         * 
* *

This implements the 'Language-Tag' production of BCP47, and * so supports grandfathered (regular and irregular) as well as * private use language tags. Stand alone private use tags are * represented as empty language and extension 'x-whatever', * and grandfathered tags are converted to their canonical replacements * where they exist. * *

Grandfathered tags with canonical replacements are as follows: * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Grandfathered tags with canonical replacements
grandfathered tagmodern replacement
art-lojbanjbo
i-amiami
i-bnnbnn
i-hakhak
i-klingontlh
i-luxlb
i-navajonv
i-pwnpwn
i-taotao
i-taytay
i-tsutsu
no-boknb
no-nynnn
sgn-BE-FRsfb
sgn-BE-NLvgt
sgn-CH-DEsgg
zh-guoyucmn
zh-hakkahak
zh-min-nannan
zh-xianghsn
* *

Grandfathered tags with no modern replacement will be * converted as follows: * * * * * * * * * * * * * * *
Grandfathered tags with no modern replacement
grandfathered tagconverts to
cel-gaulishxtg-x-cel-gaulish
en-GB-oeden-GB-x-oed
i-defaulten-x-i-default
i-enochianund-x-i-enochian
i-mingosee-x-i-mingo
zh-minnan-x-zh-min
* *

For a list of all grandfathered tags, see the * IANA Language Subtag Registry (search for "Type: grandfathered"). * *

Note: there is no guarantee that toLanguageTag * and forLanguageTag will round-trip. * * @param languageTag the language tag * @return The locale that best represents the language tag. * @throws NullPointerException if languageTag is null * @see #toLanguageTag() * @see java.util.Locale.Builder#setLanguageTag(String) * @since 1.7 */ public static Locale forLanguageTag(String languageTag) { LanguageTag tag = LanguageTag.parse(languageTag, null); InternalLocaleBuilder bldr = new InternalLocaleBuilder(); bldr.setLanguageTag(tag); BaseLocale base = bldr.getBaseLocale(); LocaleExtensions exts = bldr.getLocaleExtensions(); if (exts == null && base.getVariant().length() > 0) { exts = getCompatibilityExtensions(base.getLanguage(), base.getScript(), base.getRegion(), base.getVariant()); } return getInstance(base, exts); } /** * Returns a three-letter abbreviation of this locale's language. * If the language matches an ISO 639-1 two-letter code, the * corresponding ISO 639-2/T three-letter lowercase code is * returned. The ISO 639-2 language codes can be found on-line, * see "Codes for the Representation of Names of Languages Part 2: * Alpha-3 Code". If the locale specifies a three-letter * language, the language is returned as is. If the locale does * not specify a language the empty string is returned. * * @return A three-letter abbreviation of this locale's language. * @exception MissingResourceException Throws MissingResourceException if * three-letter language abbreviation is not available for this locale. */ public String getISO3Language() throws MissingResourceException { String lang = baseLocale.getLanguage(); if (lang.length() == 3) { return lang; } String language3 = getISO3Code(lang, LocaleISOData.isoLanguageTable); if (language3 == null) { throw new MissingResourceException("Couldn't find 3-letter language code for " + lang, "FormatData_" + toString(), "ShortLanguage"); } return language3; } /** * Returns a three-letter abbreviation for this locale's country. * If the country matches an ISO 3166-1 alpha-2 code, the * corresponding ISO 3166-1 alpha-3 uppercase code is returned. * If the locale doesn't specify a country, this will be the empty * string. * *

The ISO 3166-1 codes can be found on-line. * * @return A three-letter abbreviation of this locale's country. * @exception MissingResourceException Throws MissingResourceException if the * three-letter country abbreviation is not available for this locale. */ public String getISO3Country() throws MissingResourceException { String country3 = getISO3Code(baseLocale.getRegion(), LocaleISOData.isoCountryTable); if (country3 == null) { throw new MissingResourceException("Couldn't find 3-letter country code for " + baseLocale.getRegion(), "FormatData_" + toString(), "ShortCountry"); } return country3; } private static String getISO3Code(String iso2Code, String table) { int codeLength = iso2Code.length(); if (codeLength == 0) { return ""; } int tableLength = table.length(); int index = tableLength; if (codeLength == 2) { char c1 = iso2Code.charAt(0); char c2 = iso2Code.charAt(1); for (index = 0; index < tableLength; index += 5) { if (table.charAt(index) == c1 && table.charAt(index + 1) == c2) { break; } } } return index < tableLength ? table.substring(index + 2, index + 5) : null; } /** * Returns a name for the locale's language that is appropriate for display to the * user. * If possible, the name returned will be localized for the default * {@link Locale.Category#DISPLAY DISPLAY} locale. * For example, if the locale is fr_FR and the default * {@link Locale.Category#DISPLAY DISPLAY} locale * is en_US, getDisplayLanguage() will return "French"; if the locale is en_US and * the default {@link Locale.Category#DISPLAY DISPLAY} locale is fr_FR, * getDisplayLanguage() will return "anglais". * If the name returned cannot be localized for the default * {@link Locale.Category#DISPLAY DISPLAY} locale, * (say, we don't have a Japanese name for Croatian), * this function falls back on the English name, and uses the ISO code as a last-resort * value. If the locale doesn't specify a language, this function returns the empty string. * * @return The name of the display language. */ public final String getDisplayLanguage() { return getDisplayLanguage(getDefault(Category.DISPLAY)); } /** * Returns a name for the locale's language that is appropriate for display to the * user. * If possible, the name returned will be localized according to inLocale. * For example, if the locale is fr_FR and inLocale * is en_US, getDisplayLanguage() will return "French"; if the locale is en_US and * inLocale is fr_FR, getDisplayLanguage() will return "anglais". * If the name returned cannot be localized according to inLocale, * (say, we don't have a Japanese name for Croatian), * this function falls back on the English name, and finally * on the ISO code as a last-resort value. If the locale doesn't specify a language, * this function returns the empty string. * * @param inLocale The locale for which to retrieve the display language. * @return The name of the display language appropriate to the given locale. * @exception NullPointerException if inLocale is null */ public String getDisplayLanguage(Locale inLocale) { return getDisplayString(baseLocale.getLanguage(), null, inLocale, DISPLAY_LANGUAGE); } /** * Returns a name for the locale's script that is appropriate for display to * the user. If possible, the name will be localized for the default * {@link Locale.Category#DISPLAY DISPLAY} locale. Returns * the empty string if this locale doesn't specify a script code. * * @return the display name of the script code for the current default * {@link Locale.Category#DISPLAY DISPLAY} locale * @since 1.7 */ public String getDisplayScript() { return getDisplayScript(getDefault(Category.DISPLAY)); } /** * Returns a name for the locale's script that is appropriate * for display to the user. If possible, the name will be * localized for the given locale. Returns the empty string if * this locale doesn't specify a script code. * * @param inLocale The locale for which to retrieve the display script. * @return the display name of the script code for the current default * {@link Locale.Category#DISPLAY DISPLAY} locale * @throws NullPointerException if inLocale is null * @since 1.7 */ public String getDisplayScript(Locale inLocale) { return getDisplayString(baseLocale.getScript(), null, inLocale, DISPLAY_SCRIPT); } /** * Returns a name for the locale's country that is appropriate for display to the * user. * If possible, the name returned will be localized for the default * {@link Locale.Category#DISPLAY DISPLAY} locale. * For example, if the locale is fr_FR and the default * {@link Locale.Category#DISPLAY DISPLAY} locale * is en_US, getDisplayCountry() will return "France"; if the locale is en_US and * the default {@link Locale.Category#DISPLAY DISPLAY} locale is fr_FR, * getDisplayCountry() will return "Etats-Unis". * If the name returned cannot be localized for the default * {@link Locale.Category#DISPLAY DISPLAY} locale, * (say, we don't have a Japanese name for Croatia), * this function falls back on the English name, and uses the ISO code as a last-resort * value. If the locale doesn't specify a country, this function returns the empty string. * * @return The name of the country appropriate to the locale. */ public final String getDisplayCountry() { return getDisplayCountry(getDefault(Category.DISPLAY)); } /** * Returns a name for the locale's country that is appropriate for display to the * user. * If possible, the name returned will be localized according to inLocale. * For example, if the locale is fr_FR and inLocale * is en_US, getDisplayCountry() will return "France"; if the locale is en_US and * inLocale is fr_FR, getDisplayCountry() will return "Etats-Unis". * If the name returned cannot be localized according to inLocale. * (say, we don't have a Japanese name for Croatia), * this function falls back on the English name, and finally * on the ISO code as a last-resort value. If the locale doesn't specify a country, * this function returns the empty string. * * @param inLocale The locale for which to retrieve the display country. * @return The name of the country appropriate to the given locale. * @exception NullPointerException if inLocale is null */ public String getDisplayCountry(Locale inLocale) { return getDisplayString(baseLocale.getRegion(), null, inLocale, DISPLAY_COUNTRY); } private String getDisplayString(String code, String cat, Locale inLocale, int type) { Objects.requireNonNull(inLocale); Objects.requireNonNull(code); if (code.isEmpty()) { return ""; } LocaleServiceProviderPool pool = LocaleServiceProviderPool.getPool(LocaleNameProvider.class); String rbKey = (type == DISPLAY_VARIANT ? "%%"+code : code); String result = pool.getLocalizedObject( LocaleNameGetter.INSTANCE, inLocale, rbKey, type, code, cat); return result != null ? result : code; } /** * Returns a name for the locale's variant code that is appropriate for display to the * user. If possible, the name will be localized for the default * {@link Locale.Category#DISPLAY DISPLAY} locale. If the locale * doesn't specify a variant code, this function returns the empty string. * * @return The name of the display variant code appropriate to the locale. */ public final String getDisplayVariant() { return getDisplayVariant(getDefault(Category.DISPLAY)); } /** * Returns a name for the locale's variant code that is appropriate for display to the * user. If possible, the name will be localized for inLocale. If the locale * doesn't specify a variant code, this function returns the empty string. * * @param inLocale The locale for which to retrieve the display variant code. * @return The name of the display variant code appropriate to the given locale. * @exception NullPointerException if inLocale is null */ public String getDisplayVariant(Locale inLocale) { if (baseLocale.getVariant().length() == 0) return ""; LocaleResources lr = LocaleProviderAdapter .getResourceBundleBased() .getLocaleResources(inLocale); String names[] = getDisplayVariantArray(inLocale); // Get the localized patterns for formatting a list, and use // them to format the list. return formatList(names, lr.getLocaleName("ListCompositionPattern")); } /** * Returns a name for the locale that is appropriate for display to the * user. This will be the values returned by getDisplayLanguage(), * getDisplayScript(), getDisplayCountry(), getDisplayVariant() and * optional Unicode extensions * assembled into a single string. The non-empty values are used in order, with * the second and subsequent names in parentheses. For example: *

* language (script, country, variant(, extension)*)
* language (country(, extension)*)
* language (variant(, extension)*)
* script (country(, extension)*)
* country (extension)*
*
* depending on which fields are specified in the locale. The field * separator in the above parentheses, denoted as a comma character, may * be localized depending on the locale. If the language, script, country, * and variant fields are all empty, this function returns the empty string. * * @return The name of the locale appropriate to display. */ public final String getDisplayName() { return getDisplayName(getDefault(Category.DISPLAY)); } /** * Returns a name for the locale that is appropriate for display * to the user. This will be the values returned by * getDisplayLanguage(), getDisplayScript(),getDisplayCountry() * getDisplayVariant(), and optional * Unicode extensions assembled into a single string. The non-empty * values are used in order, with the second and subsequent names in * parentheses. For example: *
* language (script, country, variant(, extension)*)
* language (country(, extension)*)
* language (variant(, extension)*)
* script (country(, extension)*)
* country (extension)*
*
* depending on which fields are specified in the locale. The field * separator in the above parentheses, denoted as a comma character, may * be localized depending on the locale. If the language, script, country, * and variant fields are all empty, this function returns the empty string. * * @param inLocale The locale for which to retrieve the display name. * @return The name of the locale appropriate to display. * @throws NullPointerException if inLocale is null */ public String getDisplayName(Locale inLocale) { LocaleResources lr = LocaleProviderAdapter .getResourceBundleBased() .getLocaleResources(inLocale); String languageName = getDisplayLanguage(inLocale); String scriptName = getDisplayScript(inLocale); String countryName = getDisplayCountry(inLocale); String[] variantNames = getDisplayVariantArray(inLocale); // Get the localized patterns for formatting a display name. String displayNamePattern = lr.getLocaleName("DisplayNamePattern"); String listCompositionPattern = lr.getLocaleName("ListCompositionPattern"); // The display name consists of a main name, followed by qualifiers. // Typically, the format is "MainName (Qualifier, Qualifier)" but this // depends on what pattern is stored in the display locale. String mainName = null; String[] qualifierNames = null; // The main name is the language, or if there is no language, the script, // then if no script, the country. If there is no language/script/country // (an anomalous situation) then the display name is simply the variant's // display name. if (languageName.length() == 0 && scriptName.length() == 0 && countryName.length() == 0) { if (variantNames.length == 0) { return ""; } else { return formatList(variantNames, listCompositionPattern); } } ArrayList names = new ArrayList<>(4); if (languageName.length() != 0) { names.add(languageName); } if (scriptName.length() != 0) { names.add(scriptName); } if (countryName.length() != 0) { names.add(countryName); } if (variantNames.length != 0) { names.addAll(Arrays.asList(variantNames)); } // add Unicode extensions if (localeExtensions != null) { localeExtensions.getUnicodeLocaleAttributes().stream() .map(key -> getDisplayString(key, null, inLocale, DISPLAY_UEXT_KEY)) .forEach(names::add); localeExtensions.getUnicodeLocaleKeys().stream() .map(key -> getDisplayKeyTypeExtensionString(key, lr, inLocale)) .forEach(names::add); } // The first one in the main name mainName = names.get(0); // Others are qualifiers int numNames = names.size(); qualifierNames = (numNames > 1) ? names.subList(1, numNames).toArray(new String[numNames - 1]) : new String[0]; // Create an array whose first element is the number of remaining // elements. This serves as a selector into a ChoiceFormat pattern from // the resource. The second and third elements are the main name and // the qualifier; if there are no qualifiers, the third element is // unused by the format pattern. Object[] displayNames = { qualifierNames.length != 0 ? 2 : 1, mainName, // We could also just call formatList() and have it handle the empty // list case, but this is more efficient, and we want it to be // efficient since all the language-only locales will not have any // qualifiers. qualifierNames.length != 0 ? formatList(qualifierNames, listCompositionPattern) : null }; if (displayNamePattern != null) { return new MessageFormat(displayNamePattern).format(displayNames); } else { // If we cannot get the message format pattern, then we use a simple // hard-coded pattern. This should not occur in practice unless the // installation is missing some core files (FormatData etc.). StringBuilder result = new StringBuilder(); result.append((String)displayNames[1]); if (displayNames.length > 2) { result.append(" ("); result.append((String)displayNames[2]); result.append(')'); } return result.toString(); } } /** * Overrides Cloneable. */ @Override public Object clone() { try { Locale that = (Locale)super.clone(); return that; } catch (CloneNotSupportedException e) { throw new InternalError(e); } } /** * Override hashCode. * Since Locales are often used in hashtables, caches the value * for speed. */ @Override public int hashCode() { int hc = hashCodeValue; if (hc == 0) { hc = baseLocale.hashCode(); if (localeExtensions != null) { hc ^= localeExtensions.hashCode(); } hashCodeValue = hc; } return hc; } // Overrides /** * Returns true if this Locale is equal to another object. A Locale is * deemed equal to another Locale with identical language, script, country, * variant and extensions, and unequal to all other objects. * * @return true if this Locale is equal to the specified object. */ @Override public boolean equals(Object obj) { if (this == obj) // quick check return true; if (!(obj instanceof Locale)) return false; BaseLocale otherBase = ((Locale)obj).baseLocale; if (!baseLocale.equals(otherBase)) { return false; } if (localeExtensions == null) { return ((Locale)obj).localeExtensions == null; } return localeExtensions.equals(((Locale)obj).localeExtensions); } // ================= privates ===================================== private transient BaseLocale baseLocale; private transient LocaleExtensions localeExtensions; /** * Calculated hashcode */ private transient volatile int hashCodeValue; private static volatile Locale defaultLocale = initDefault(); private static volatile Locale defaultDisplayLocale; private static volatile Locale defaultFormatLocale; private transient volatile String languageTag; /** * Return an array of the display names of the variant. * @param bundle the ResourceBundle to use to get the display names * @return an array of display names, possible of zero length. */ private String[] getDisplayVariantArray(Locale inLocale) { // Split the variant name into tokens separated by '_'. StringTokenizer tokenizer = new StringTokenizer(baseLocale.getVariant(), "_"); String[] names = new String[tokenizer.countTokens()]; // For each variant token, lookup the display name. If // not found, use the variant name itself. for (int i=0; i TimeZoneNameUtility.retrieveGenericDisplayName(id, TimeZone.LONG, inLocale)) .orElse(type); break; } ret = MessageFormat.format(lr.getLocaleName("ListKeyTypePattern"), getDisplayString(key, null, inLocale, DISPLAY_UEXT_KEY), Optional.ofNullable(displayType).orElse(type)); } return ret; } /** * Format a list using given pattern strings. * If either of the patterns is null, then a the list is * formatted by concatenation with the delimiter ','. * @param stringList the list of strings to be formatted. * and formatting them into a list. * @param pattern should take 2 arguments for reduction * @return a string representing the list. */ private static String formatList(String[] stringList, String pattern) { // If we have no list patterns, compose the list in a simple, // non-localized way. if (pattern == null) { return Arrays.stream(stringList).collect(Collectors.joining(",")); } switch (stringList.length) { case 0: return ""; case 1: return stringList[0]; default: return Arrays.stream(stringList).reduce("", (s1, s2) -> { if (s1.equals("")) { return s2; } if (s2.equals("")) { return s1; } return MessageFormat.format(pattern, s1, s2); }); } } // Duplicate of sun.util.locale.UnicodeLocaleExtension.isKey in order to // avoid its class loading. private static boolean isUnicodeExtensionKey(String s) { // 2alphanum return (s.length() == 2) && LocaleUtils.isAlphaNumericString(s); } /** * @serialField language String * language subtag in lower case. * (See getLanguage()) * @serialField country String * country subtag in upper case. * (See getCountry()) * @serialField variant String * variant subtags separated by LOWLINE characters. * (See getVariant()) * @serialField hashcode int * deprecated, for forward compatibility only * @serialField script String * script subtag in title case * (See getScript()) * @serialField extensions String * canonical representation of extensions, that is, * BCP47 extensions in alphabetical order followed by * BCP47 private use subtags, all in lower case letters * separated by HYPHEN-MINUS characters. * (See getExtensionKeys(), * getExtension(char)) */ private static final ObjectStreamField[] serialPersistentFields = { new ObjectStreamField("language", String.class), new ObjectStreamField("country", String.class), new ObjectStreamField("variant", String.class), new ObjectStreamField("hashcode", int.class), new ObjectStreamField("script", String.class), new ObjectStreamField("extensions", String.class), }; /** * Serializes this Locale to the specified ObjectOutputStream. * @param out the ObjectOutputStream to write * @throws IOException * @since 1.7 */ private void writeObject(ObjectOutputStream out) throws IOException { ObjectOutputStream.PutField fields = out.putFields(); fields.put("language", baseLocale.getLanguage()); fields.put("script", baseLocale.getScript()); fields.put("country", baseLocale.getRegion()); fields.put("variant", baseLocale.getVariant()); fields.put("extensions", localeExtensions == null ? "" : localeExtensions.getID()); fields.put("hashcode", -1); // place holder just for backward support out.writeFields(); } /** * Deserializes this Locale. * @param in the ObjectInputStream to read * @throws IOException * @throws ClassNotFoundException * @throws IllformedLocaleException * @since 1.7 */ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { ObjectInputStream.GetField fields = in.readFields(); String language = (String)fields.get("language", ""); String script = (String)fields.get("script", ""); String country = (String)fields.get("country", ""); String variant = (String)fields.get("variant", ""); String extStr = (String)fields.get("extensions", ""); baseLocale = BaseLocale.getInstance(convertOldISOCodes(language), script, country, variant); if (extStr.length() > 0) { try { InternalLocaleBuilder bldr = new InternalLocaleBuilder(); bldr.setExtensions(extStr); localeExtensions = bldr.getLocaleExtensions(); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage()); } } else { localeExtensions = null; } } /** * Returns a cached Locale instance equivalent to * the deserialized Locale. When serialized * language, country and variant fields read from the object data stream * are exactly "ja", "JP", "JP" or "th", "TH", "TH" and script/extensions * fields are empty, this method supplies UNICODE_LOCALE_EXTENSION * "ca"/"japanese" (calendar type is "japanese") or "nu"/"thai" (number script * type is "thai"). See Special Cases * for more information. * * @return an instance of Locale equivalent to * the deserialized Locale. * @throws java.io.ObjectStreamException */ private Object readResolve() throws java.io.ObjectStreamException { return getInstance(baseLocale.getLanguage(), baseLocale.getScript(), baseLocale.getRegion(), baseLocale.getVariant(), localeExtensions); } private static volatile String[] isoLanguages; private static volatile String[] isoCountries; private static String convertOldISOCodes(String language) { // we accept both the old and the new ISO codes for the languages whose ISO // codes have changed, but we always store the OLD code, for backward compatibility language = LocaleUtils.toLowerString(language).intern(); if (language == "he") { return "iw"; } else if (language == "yi") { return "ji"; } else if (language == "id") { return "in"; } else { return language; } } private static LocaleExtensions getCompatibilityExtensions(String language, String script, String country, String variant) { LocaleExtensions extensions = null; // Special cases for backward compatibility support if (LocaleUtils.caseIgnoreMatch(language, "ja") && script.length() == 0 && LocaleUtils.caseIgnoreMatch(country, "jp") && "JP".equals(variant)) { // ja_JP_JP -> u-ca-japanese (calendar = japanese) extensions = LocaleExtensions.CALENDAR_JAPANESE; } else if (LocaleUtils.caseIgnoreMatch(language, "th") && script.length() == 0 && LocaleUtils.caseIgnoreMatch(country, "th") && "TH".equals(variant)) { // th_TH_TH -> u-nu-thai (numbersystem = thai) extensions = LocaleExtensions.NUMBER_THAI; } return extensions; } /** * Obtains a localized locale names from a LocaleNameProvider * implementation. */ private static class LocaleNameGetter implements LocaleServiceProviderPool.LocalizedObjectGetter { private static final LocaleNameGetter INSTANCE = new LocaleNameGetter(); @Override public String getObject(LocaleNameProvider localeNameProvider, Locale locale, String key, Object... params) { assert params.length == 3; int type = (Integer)params[0]; String code = (String)params[1]; String cat = (String)params[2]; switch(type) { case DISPLAY_LANGUAGE: return localeNameProvider.getDisplayLanguage(code, locale); case DISPLAY_COUNTRY: return localeNameProvider.getDisplayCountry(code, locale); case DISPLAY_VARIANT: return localeNameProvider.getDisplayVariant(code, locale); case DISPLAY_SCRIPT: return localeNameProvider.getDisplayScript(code, locale); case DISPLAY_UEXT_KEY: return localeNameProvider.getDisplayUnicodeExtensionKey(code, locale); case DISPLAY_UEXT_TYPE: return localeNameProvider.getDisplayUnicodeExtensionType(code, cat, locale); default: assert false; // shouldn't happen } return null; } } /** * Enum for locale categories. These locale categories are used to get/set * the default locale for the specific functionality represented by the * category. * * @see #getDefault(Locale.Category) * @see #setDefault(Locale.Category, Locale) * @since 1.7 */ public enum Category { /** * Category used to represent the default locale for * displaying user interfaces. */ DISPLAY("user.language.display", "user.script.display", "user.country.display", "user.variant.display", "user.extensions.display"), /** * Category used to represent the default locale for * formatting dates, numbers, and/or currencies. */ FORMAT("user.language.format", "user.script.format", "user.country.format", "user.variant.format", "user.extensions.format"); Category(String languageKey, String scriptKey, String countryKey, String variantKey, String extensionsKey) { this.languageKey = languageKey; this.scriptKey = scriptKey; this.countryKey = countryKey; this.variantKey = variantKey; this.extensionsKey = extensionsKey; } final String languageKey; final String scriptKey; final String countryKey; final String variantKey; final String extensionsKey; } /** * Builder is used to build instances of Locale * from values configured by the setters. Unlike the Locale * constructors, the Builder checks if a value configured by a * setter satisfies the syntax requirements defined by the Locale * class. A Locale object created by a Builder is * well-formed and can be transformed to a well-formed IETF BCP 47 language tag * without losing information. * *

Note: The Locale class does not provide any * syntactic restrictions on variant, while BCP 47 requires each variant * subtag to be 5 to 8 alphanumerics or a single numeric followed by 3 * alphanumerics. The method setVariant throws * IllformedLocaleException for a variant that does not satisfy * this restriction. If it is necessary to support such a variant, use a * Locale constructor. However, keep in mind that a Locale * object created this way might lose the variant information when * transformed to a BCP 47 language tag. * *

The following example shows how to create a Locale object * with the Builder. *

*
     *     Locale aLocale = new Builder().setLanguage("sr").setScript("Latn").setRegion("RS").build();
     * 
*
* *

Builders can be reused; clear() resets all * fields to their default values. * * @see Locale#forLanguageTag * @since 1.7 */ public static final class Builder { private final InternalLocaleBuilder localeBuilder; /** * Constructs an empty Builder. The default value of all * fields, extensions, and private use information is the * empty string. */ public Builder() { localeBuilder = new InternalLocaleBuilder(); } /** * Resets the Builder to match the provided * locale. Existing state is discarded. * *

All fields of the locale must be well-formed, see {@link Locale}. * *

Locales with any ill-formed fields cause * IllformedLocaleException to be thrown, except for the * following three cases which are accepted for compatibility * reasons:

    *
  • Locale("ja", "JP", "JP") is treated as "ja-JP-u-ca-japanese" *
  • Locale("th", "TH", "TH") is treated as "th-TH-u-nu-thai" *
  • Locale("no", "NO", "NY") is treated as "nn-NO"
* * @param locale the locale * @return This builder. * @throws IllformedLocaleException if locale has * any ill-formed fields. * @throws NullPointerException if locale is null. */ public Builder setLocale(Locale locale) { try { localeBuilder.setLocale(locale.baseLocale, locale.localeExtensions); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Resets the Builder to match the provided IETF BCP 47 * language tag. Discards the existing state. Null and the * empty string cause the builder to be reset, like {@link * #clear}. Grandfathered tags (see {@link * Locale#forLanguageTag}) are converted to their canonical * form before being processed. Otherwise, the language tag * must be well-formed (see {@link Locale}) or an exception is * thrown (unlike Locale.forLanguageTag, which * just discards ill-formed and following portions of the * tag). * * @param languageTag the language tag * @return This builder. * @throws IllformedLocaleException if languageTag is ill-formed * @see Locale#forLanguageTag(String) */ public Builder setLanguageTag(String languageTag) { ParseStatus sts = new ParseStatus(); LanguageTag tag = LanguageTag.parse(languageTag, sts); if (sts.isError()) { throw new IllformedLocaleException(sts.getErrorMessage(), sts.getErrorIndex()); } localeBuilder.setLanguageTag(tag); return this; } /** * Sets the language. If language is the empty string or * null, the language in this Builder is removed. Otherwise, * the language must be well-formed * or an exception is thrown. * *

The typical language value is a two or three-letter language * code as defined in ISO639. * * @param language the language * @return This builder. * @throws IllformedLocaleException if language is ill-formed */ public Builder setLanguage(String language) { try { localeBuilder.setLanguage(language); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Sets the script. If script is null or the empty string, * the script in this Builder is removed. * Otherwise, the script must be well-formed or an * exception is thrown. * *

The typical script value is a four-letter script code as defined by ISO 15924. * * @param script the script * @return This builder. * @throws IllformedLocaleException if script is ill-formed */ public Builder setScript(String script) { try { localeBuilder.setScript(script); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Sets the region. If region is null or the empty string, the region * in this Builder is removed. Otherwise, * the region must be well-formed or an * exception is thrown. * *

The typical region value is a two-letter ISO 3166 code or a * three-digit UN M.49 area code. * *

The country value in the Locale created by the * Builder is always normalized to upper case. * * @param region the region * @return This builder. * @throws IllformedLocaleException if region is ill-formed */ public Builder setRegion(String region) { try { localeBuilder.setRegion(region); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Sets the variant. If variant is null or the empty string, the * variant in this Builder is removed. Otherwise, it * must consist of one or more well-formed * subtags, or an exception is thrown. * *

Note: This method checks if variant * satisfies the IETF BCP 47 variant subtag's syntax requirements, * and normalizes the value to lowercase letters. However, * the Locale class does not impose any syntactic * restriction on variant, and the variant value in * Locale is case sensitive. To set such a variant, * use a Locale constructor. * * @param variant the variant * @return This builder. * @throws IllformedLocaleException if variant is ill-formed */ public Builder setVariant(String variant) { try { localeBuilder.setVariant(variant); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Sets the extension for the given key. If the value is null or the * empty string, the extension is removed. Otherwise, the extension * must be well-formed or an exception * is thrown. * *

Note: The key {@link Locale#UNICODE_LOCALE_EXTENSION * UNICODE_LOCALE_EXTENSION} ('u') is used for the Unicode locale extension. * Setting a value for this key replaces any existing Unicode locale key/type * pairs with those defined in the extension. * *

Note: The key {@link Locale#PRIVATE_USE_EXTENSION * PRIVATE_USE_EXTENSION} ('x') is used for the private use code. To be * well-formed, the value for this key needs only to have subtags of one to * eight alphanumeric characters, not two to eight as in the general case. * * @param key the extension key * @param value the extension value * @return This builder. * @throws IllformedLocaleException if key is illegal * or value is ill-formed * @see #setUnicodeLocaleKeyword(String, String) */ public Builder setExtension(char key, String value) { try { localeBuilder.setExtension(key, value); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Sets the Unicode locale keyword type for the given key. If the type * is null, the Unicode keyword is removed. Otherwise, the key must be * non-null and both key and type must be well-formed or an exception * is thrown. * *

Keys and types are converted to lower case. * *

Note:Setting the 'u' extension via {@link #setExtension} * replaces all Unicode locale keywords with those defined in the * extension. * * @param key the Unicode locale key * @param type the Unicode locale type * @return This builder. * @throws IllformedLocaleException if key or type * is ill-formed * @throws NullPointerException if key is null * @see #setExtension(char, String) */ public Builder setUnicodeLocaleKeyword(String key, String type) { try { localeBuilder.setUnicodeLocaleKeyword(key, type); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Adds a unicode locale attribute, if not already present, otherwise * has no effect. The attribute must not be null and must be well-formed or an exception * is thrown. * * @param attribute the attribute * @return This builder. * @throws NullPointerException if attribute is null * @throws IllformedLocaleException if attribute is ill-formed * @see #setExtension(char, String) */ public Builder addUnicodeLocaleAttribute(String attribute) { try { localeBuilder.addUnicodeLocaleAttribute(attribute); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Removes a unicode locale attribute, if present, otherwise has no * effect. The attribute must not be null and must be well-formed or an exception * is thrown. * *

Attribute comparison for removal is case-insensitive. * * @param attribute the attribute * @return This builder. * @throws NullPointerException if attribute is null * @throws IllformedLocaleException if attribute is ill-formed * @see #setExtension(char, String) */ public Builder removeUnicodeLocaleAttribute(String attribute) { Objects.requireNonNull(attribute); try { localeBuilder.removeUnicodeLocaleAttribute(attribute); } catch (LocaleSyntaxException e) { throw new IllformedLocaleException(e.getMessage(), e.getErrorIndex()); } return this; } /** * Resets the builder to its initial, empty state. * * @return This builder. */ public Builder clear() { localeBuilder.clear(); return this; } /** * Resets the extensions to their initial, empty state. * Language, script, region and variant are unchanged. * * @return This builder. * @see #setExtension(char, String) */ public Builder clearExtensions() { localeBuilder.clearExtensions(); return this; } /** * Returns an instance of Locale created from the fields set * on this builder. * *

This applies the conversions listed in {@link Locale#forLanguageTag} * when constructing a Locale. (Grandfathered tags are handled in * {@link #setLanguageTag}.) * * @return A Locale. */ public Locale build() { BaseLocale baseloc = localeBuilder.getBaseLocale(); LocaleExtensions extensions = localeBuilder.getLocaleExtensions(); if (extensions == null && baseloc.getVariant().length() > 0) { extensions = getCompatibilityExtensions(baseloc.getLanguage(), baseloc.getScript(), baseloc.getRegion(), baseloc.getVariant()); } return Locale.getInstance(baseloc, extensions); } } /** * This enum provides constants to select a filtering mode for locale * matching. Refer to RFC 4647 * Matching of Language Tags for details. * *

As an example, think of two Language Priority Lists each of which * includes only one language range and a set of following language tags: * *

     *    de (German)
     *    de-DE (German, Germany)
     *    de-Deva (German, in Devanagari script)
     *    de-Deva-DE (German, in Devanagari script, Germany)
     *    de-DE-1996 (German, Germany, orthography of 1996)
     *    de-Latn-DE (German, in Latin script, Germany)
     *    de-Latn-DE-1996 (German, in Latin script, Germany, orthography of 1996)
     * 
* * The filtering method will behave as follows: * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Filtering method behavior
Filtering ModeLanguage Priority List: {@code "de-DE"}Language Priority List: {@code "de-*-DE"}
* {@link FilteringMode#AUTOSELECT_FILTERING AUTOSELECT_FILTERING} * * Performs basic filtering and returns {@code "de-DE"} and * {@code "de-DE-1996"}. * * Performs extended filtering and returns {@code "de-DE"}, * {@code "de-Deva-DE"}, {@code "de-DE-1996"}, {@code "de-Latn-DE"}, and * {@code "de-Latn-DE-1996"}. *
* {@link FilteringMode#EXTENDED_FILTERING EXTENDED_FILTERING} * * Performs extended filtering and returns {@code "de-DE"}, * {@code "de-Deva-DE"}, {@code "de-DE-1996"}, {@code "de-Latn-DE"}, and * {@code "de-Latn-DE-1996"}. * Same as above.
* {@link FilteringMode#IGNORE_EXTENDED_RANGES IGNORE_EXTENDED_RANGES} * * Performs basic filtering and returns {@code "de-DE"} and * {@code "de-DE-1996"}. * * Performs basic filtering and returns {@code null} because * nothing matches. *
* {@link FilteringMode#MAP_EXTENDED_RANGES MAP_EXTENDED_RANGES} * Same as above. * Performs basic filtering and returns {@code "de-DE"} and * {@code "de-DE-1996"} because {@code "de-*-DE"} is mapped to * {@code "de-DE"}. *
* {@link FilteringMode#REJECT_EXTENDED_RANGES REJECT_EXTENDED_RANGES} * Same as above. * Throws {@link IllegalArgumentException} because {@code "de-*-DE"} is * not a valid basic language range. *
* * @see #filter(List, Collection, FilteringMode) * @see #filterTags(List, Collection, FilteringMode) * * @since 1.8 */ public static enum FilteringMode { /** * Specifies automatic filtering mode based on the given Language * Priority List consisting of language ranges. If all of the ranges * are basic, basic filtering is selected. Otherwise, extended * filtering is selected. */ AUTOSELECT_FILTERING, /** * Specifies extended filtering. */ EXTENDED_FILTERING, /** * Specifies basic filtering: Note that any extended language ranges * included in the given Language Priority List are ignored. */ IGNORE_EXTENDED_RANGES, /** * Specifies basic filtering: If any extended language ranges are * included in the given Language Priority List, they are mapped to the * basic language range. Specifically, a language range starting with a * subtag {@code "*"} is treated as a language range {@code "*"}. For * example, {@code "*-US"} is treated as {@code "*"}. If {@code "*"} is * not the first subtag, {@code "*"} and extra {@code "-"} are removed. * For example, {@code "ja-*-JP"} is mapped to {@code "ja-JP"}. */ MAP_EXTENDED_RANGES, /** * Specifies basic filtering: If any extended language ranges are * included in the given Language Priority List, the list is rejected * and the filtering method throws {@link IllegalArgumentException}. */ REJECT_EXTENDED_RANGES }; /** * This class expresses a Language Range defined in * RFC 4647 Matching of * Language Tags. A language range is an identifier which is used to * select language tag(s) meeting specific requirements by using the * mechanisms described in Locale * Matching. A list which represents a user's preferences and consists * of language ranges is called a Language Priority List. * *

There are two types of language ranges: basic and extended. In RFC * 4647, the syntax of language ranges is expressed in * ABNF as follows: *

*
     *     basic-language-range    = (1*8ALPHA *("-" 1*8alphanum)) / "*"
     *     extended-language-range = (1*8ALPHA / "*")
     *                               *("-" (1*8alphanum / "*"))
     *     alphanum                = ALPHA / DIGIT
     * 
*
* For example, {@code "en"} (English), {@code "ja-JP"} (Japanese, Japan), * {@code "*"} (special language range which matches any language tag) are * basic language ranges, whereas {@code "*-CH"} (any languages, * Switzerland), {@code "es-*"} (Spanish, any regions), and * {@code "zh-Hant-*"} (Traditional Chinese, any regions) are extended * language ranges. * * @see #filter * @see #filterTags * @see #lookup * @see #lookupTag * * @since 1.8 */ public static final class LanguageRange { /** * A constant holding the maximum value of weight, 1.0, which indicates * that the language range is a good fit for the user. */ public static final double MAX_WEIGHT = 1.0; /** * A constant holding the minimum value of weight, 0.0, which indicates * that the language range is not a good fit for the user. */ public static final double MIN_WEIGHT = 0.0; private final String range; private final double weight; private volatile int hash; /** * Constructs a {@code LanguageRange} using the given {@code range}. * Note that no validation is done against the IANA Language Subtag * Registry at time of construction. * *

This is equivalent to {@code LanguageRange(range, MAX_WEIGHT)}. * * @param range a language range * @throws NullPointerException if the given {@code range} is * {@code null} * @throws IllegalArgumentException if the given {@code range} does not * comply with the syntax of the language range mentioned in RFC 4647 */ public LanguageRange(String range) { this(range, MAX_WEIGHT); } /** * Constructs a {@code LanguageRange} using the given {@code range} and * {@code weight}. Note that no validation is done against the IANA * Language Subtag Registry at time of construction. * * @param range a language range * @param weight a weight value between {@code MIN_WEIGHT} and * {@code MAX_WEIGHT} * @throws NullPointerException if the given {@code range} is * {@code null} * @throws IllegalArgumentException if the given {@code range} does not * comply with the syntax of the language range mentioned in RFC 4647 * or if the given {@code weight} is less than {@code MIN_WEIGHT} * or greater than {@code MAX_WEIGHT} */ public LanguageRange(String range, double weight) { if (range == null) { throw new NullPointerException(); } if (weight < MIN_WEIGHT || weight > MAX_WEIGHT) { throw new IllegalArgumentException("weight=" + weight); } range = range.toLowerCase(Locale.ROOT); // Do syntax check. boolean isIllFormed = false; String[] subtags = range.split("-"); if (isSubtagIllFormed(subtags[0], true) || range.endsWith("-")) { isIllFormed = true; } else { for (int i = 1; i < subtags.length; i++) { if (isSubtagIllFormed(subtags[i], false)) { isIllFormed = true; break; } } } if (isIllFormed) { throw new IllegalArgumentException("range=" + range); } this.range = range; this.weight = weight; } private static boolean isSubtagIllFormed(String subtag, boolean isFirstSubtag) { if (subtag.equals("") || subtag.length() > 8) { return true; } else if (subtag.equals("*")) { return false; } char[] charArray = subtag.toCharArray(); if (isFirstSubtag) { // ALPHA for (char c : charArray) { if (c < 'a' || c > 'z') { return true; } } } else { // ALPHA / DIGIT for (char c : charArray) { if (c < '0' || (c > '9' && c < 'a') || c > 'z') { return true; } } } return false; } /** * Returns the language range of this {@code LanguageRange}. * * @return the language range. */ public String getRange() { return range; } /** * Returns the weight of this {@code LanguageRange}. * * @return the weight value. */ public double getWeight() { return weight; } /** * Parses the given {@code ranges} to generate a Language Priority List. * *

This method performs a syntactic check for each language range in * the given {@code ranges} but doesn't do validation using the IANA * Language Subtag Registry. * *

The {@code ranges} to be given can take one of the following * forms: * *

         *   "Accept-Language: ja,en;q=0.4"  (weighted list with Accept-Language prefix)
         *   "ja,en;q=0.4"                   (weighted list)
         *   "ja,en"                         (prioritized list)
         * 
* * In a weighted list, each language range is given a weight value. * The weight value is identical to the "quality value" in * RFC 2616, and it * expresses how much the user prefers the language. A weight value is * specified after a corresponding language range followed by * {@code ";q="}, and the default weight value is {@code MAX_WEIGHT} * when it is omitted. * *

Unlike a weighted list, language ranges in a prioritized list * are sorted in the descending order based on its priority. The first * language range has the highest priority and meets the user's * preference most. * *

In either case, language ranges are sorted in descending order in * the Language Priority List based on priority or weight. If a * language range appears in the given {@code ranges} more than once, * only the first one is included on the Language Priority List. * *

The returned list consists of language ranges from the given * {@code ranges} and their equivalents found in the IANA Language * Subtag Registry. For example, if the given {@code ranges} is * {@code "Accept-Language: iw,en-us;q=0.7,en;q=0.3"}, the elements in * the list to be returned are: * *

         *  Range                                   Weight
         *    "iw" (older tag for Hebrew)             1.0
         *    "he" (new preferred code for Hebrew)    1.0
         *    "en-us" (English, United States)        0.7
         *    "en" (English)                          0.3
         * 
* * Two language ranges, {@code "iw"} and {@code "he"}, have the same * highest priority in the list. By adding {@code "he"} to the user's * Language Priority List, locale-matching method can find Hebrew as a * matching locale (or language tag) even if the application or system * offers only {@code "he"} as a supported locale (or language tag). * * @param ranges a list of comma-separated language ranges or a list of * language ranges in the form of the "Accept-Language" header * defined in RFC * 2616 * @return a Language Priority List consisting of language ranges * included in the given {@code ranges} and their equivalent * language ranges if available. The list is modifiable. * @throws NullPointerException if {@code ranges} is null * @throws IllegalArgumentException if a language range or a weight * found in the given {@code ranges} is ill-formed */ public static List parse(String ranges) { return LocaleMatcher.parse(ranges); } /** * Parses the given {@code ranges} to generate a Language Priority * List, and then customizes the list using the given {@code map}. * This method is equivalent to * {@code mapEquivalents(parse(ranges), map)}. * * @param ranges a list of comma-separated language ranges or a list * of language ranges in the form of the "Accept-Language" header * defined in RFC * 2616 * @param map a map containing information to customize language ranges * @return a Language Priority List with customization. The list is * modifiable. * @throws NullPointerException if {@code ranges} is null * @throws IllegalArgumentException if a language range or a weight * found in the given {@code ranges} is ill-formed * @see #parse(String) * @see #mapEquivalents */ public static List parse(String ranges, Map> map) { return mapEquivalents(parse(ranges), map); } /** * Generates a new customized Language Priority List using the given * {@code priorityList} and {@code map}. If the given {@code map} is * empty, this method returns a copy of the given {@code priorityList}. * *

In the map, a key represents a language range whereas a value is * a list of equivalents of it. {@code '*'} cannot be used in the map. * Each equivalent language range has the same weight value as its * original language range. * *

         *  An example of map:
         *    Key                            Value
         *      "zh" (Chinese)                 "zh",
         *                                     "zh-Hans"(Simplified Chinese)
         *      "zh-HK" (Chinese, Hong Kong)   "zh-HK"
         *      "zh-TW" (Chinese, Taiwan)      "zh-TW"
         * 
* * The customization is performed after modification using the IANA * Language Subtag Registry. * *

For example, if a user's Language Priority List consists of five * language ranges ({@code "zh"}, {@code "zh-CN"}, {@code "en"}, * {@code "zh-TW"}, and {@code "zh-HK"}), the newly generated Language * Priority List which is customized using the above map example will * consists of {@code "zh"}, {@code "zh-Hans"}, {@code "zh-CN"}, * {@code "zh-Hans-CN"}, {@code "en"}, {@code "zh-TW"}, and * {@code "zh-HK"}. * *

{@code "zh-HK"} and {@code "zh-TW"} aren't converted to * {@code "zh-Hans-HK"} nor {@code "zh-Hans-TW"} even if they are * included in the Language Priority List. In this example, mapping * is used to clearly distinguish Simplified Chinese and Traditional * Chinese. * *

If the {@code "zh"}-to-{@code "zh"} mapping isn't included in the * map, a simple replacement will be performed and the customized list * won't include {@code "zh"} and {@code "zh-CN"}. * * @param priorityList user's Language Priority List * @param map a map containing information to customize language ranges * @return a new Language Priority List with customization. The list is * modifiable. * @throws NullPointerException if {@code priorityList} is {@code null} * @see #parse(String, Map) */ public static List mapEquivalents( ListpriorityList, Map> map) { return LocaleMatcher.mapEquivalents(priorityList, map); } /** * Returns a hash code value for the object. * * @return a hash code value for this object. */ @Override public int hashCode() { int h = hash; if (h == 0) { h = 17; h = 37*h + range.hashCode(); long bitsWeight = Double.doubleToLongBits(weight); h = 37*h + (int)(bitsWeight ^ (bitsWeight >>> 32)); if (h != 0) { hash = h; } } return h; } /** * Compares this object to the specified object. The result is true if * and only if the argument is not {@code null} and is a * {@code LanguageRange} object that contains the same {@code range} * and {@code weight} values as this object. * * @param obj the object to compare with * @return {@code true} if this object's {@code range} and * {@code weight} are the same as the {@code obj}'s; {@code false} * otherwise. */ @Override public boolean equals(Object obj) { if (this == obj) { return true; } if (!(obj instanceof LanguageRange)) { return false; } LanguageRange other = (LanguageRange)obj; return hash == other.hash && range.equals(other.range) && weight == other.weight; } /** * Returns an informative string representation of this {@code LanguageRange} * object, consisting of language range and weight if the range is * weighted and the weight is less than the max weight. * * @return a string representation of this {@code LanguageRange} object. */ @Override public String toString() { return (weight == MAX_WEIGHT) ? range : range + ";q=" + weight; } } /** * Returns a list of matching {@code Locale} instances using the filtering * mechanism defined in RFC 4647. * * This filter operation on the given {@code locales} ensures that only * unique matching locale(s) are returned. * * @param priorityList user's Language Priority List in which each language * tag is sorted in descending order based on priority or weight * @param locales {@code Locale} instances used for matching * @param mode filtering mode * @return a list of {@code Locale} instances for matching language tags * sorted in descending order based on priority or weight, or an empty * list if nothing matches. The list is modifiable. * @throws NullPointerException if {@code priorityList} or {@code locales} * is {@code null} * @throws IllegalArgumentException if one or more extended language ranges * are included in the given list when * {@link FilteringMode#REJECT_EXTENDED_RANGES} is specified * * @since 1.8 */ public static List filter(List priorityList, Collection locales, FilteringMode mode) { return LocaleMatcher.filter(priorityList, locales, mode); } /** * Returns a list of matching {@code Locale} instances using the filtering * mechanism defined in RFC 4647. This is equivalent to * {@link #filter(List, Collection, FilteringMode)} when {@code mode} is * {@link FilteringMode#AUTOSELECT_FILTERING}. * * This filter operation on the given {@code locales} ensures that only * unique matching locale(s) are returned. * * @param priorityList user's Language Priority List in which each language * tag is sorted in descending order based on priority or weight * @param locales {@code Locale} instances used for matching * @return a list of {@code Locale} instances for matching language tags * sorted in descending order based on priority or weight, or an empty * list if nothing matches. The list is modifiable. * @throws NullPointerException if {@code priorityList} or {@code locales} * is {@code null} * * @since 1.8 */ public static List filter(List priorityList, Collection locales) { return filter(priorityList, locales, FilteringMode.AUTOSELECT_FILTERING); } /** * Returns a list of matching languages tags using the basic filtering * mechanism defined in RFC 4647. * * This filter operation on the given {@code tags} ensures that only * unique matching tag(s) are returned with preserved case. In case of * duplicate matching tags with the case difference, the first matching * tag with preserved case is returned. * For example, "de-ch" is returned out of the duplicate matching tags * "de-ch" and "de-CH", if "de-ch" is checked first for matching in the * given {@code tags}. Note that if the given {@code tags} is an unordered * {@code Collection}, the returned matching tag out of duplicate tags is * subject to change, depending on the implementation of the * {@code Collection}. * * @param priorityList user's Language Priority List in which each language * tag is sorted in descending order based on priority or weight * @param tags language tags * @param mode filtering mode * @return a list of matching language tags sorted in descending order * based on priority or weight, or an empty list if nothing matches. * The list is modifiable. * @throws NullPointerException if {@code priorityList} or {@code tags} is * {@code null} * @throws IllegalArgumentException if one or more extended language ranges * are included in the given list when * {@link FilteringMode#REJECT_EXTENDED_RANGES} is specified * * @since 1.8 */ public static List filterTags(List priorityList, Collection tags, FilteringMode mode) { return LocaleMatcher.filterTags(priorityList, tags, mode); } /** * Returns a list of matching languages tags using the basic filtering * mechanism defined in RFC 4647. This is equivalent to * {@link #filterTags(List, Collection, FilteringMode)} when {@code mode} * is {@link FilteringMode#AUTOSELECT_FILTERING}. * * This filter operation on the given {@code tags} ensures that only * unique matching tag(s) are returned with preserved case. In case of * duplicate matching tags with the case difference, the first matching * tag with preserved case is returned. * For example, "de-ch" is returned out of the duplicate matching tags * "de-ch" and "de-CH", if "de-ch" is checked first for matching in the * given {@code tags}. Note that if the given {@code tags} is an unordered * {@code Collection}, the returned matching tag out of duplicate tags is * subject to change, depending on the implementation of the * {@code Collection}. * * @param priorityList user's Language Priority List in which each language * tag is sorted in descending order based on priority or weight * @param tags language tags * @return a list of matching language tags sorted in descending order * based on priority or weight, or an empty list if nothing matches. * The list is modifiable. * @throws NullPointerException if {@code priorityList} or {@code tags} is * {@code null} * * @since 1.8 */ public static List filterTags(List priorityList, Collection tags) { return filterTags(priorityList, tags, FilteringMode.AUTOSELECT_FILTERING); } /** * Returns a {@code Locale} instance for the best-matching language * tag using the lookup mechanism defined in RFC 4647. * * @param priorityList user's Language Priority List in which each language * tag is sorted in descending order based on priority or weight * @param locales {@code Locale} instances used for matching * @return the best matching Locale instance chosen based on * priority or weight, or {@code null} if nothing matches. * @throws NullPointerException if {@code priorityList} or {@code tags} is * {@code null} * * @since 1.8 */ public static Locale lookup(List priorityList, Collection locales) { return LocaleMatcher.lookup(priorityList, locales); } /** * Returns the best-matching language tag using the lookup mechanism * defined in RFC 4647. * * This lookup operation on the given {@code tags} ensures that the * first matching tag with preserved case is returned. * * @param priorityList user's Language Priority List in which each language * tag is sorted in descending order based on priority or weight * @param tags language tangs used for matching * @return the best matching language tag chosen based on priority or * weight, or {@code null} if nothing matches. * @throws NullPointerException if {@code priorityList} or {@code tags} is * {@code null} * * @since 1.8 */ public static String lookupTag(List priorityList, Collection tags) { return LocaleMatcher.lookupTag(priorityList, tags); } }