Google Git
Sign in
android / toolchain / jdk / jdk9_jdk / 4be844f237dcacf6b59418a0a7246a07455c9fe9 / . / src / java.base / share / classes / java / util / Locale.java
blob: 45d13fa3db9e7d0e5f306771b717b588bebfa5e4 [file] [log] [blame]
/*
* Copyright (c) 1996, 2017, 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 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;
/**
* A <code>Locale</code> object represents a specific geographical, political,
* or cultural region. An operation that requires a <code>Locale</code> to perform
* its task is called <em>locale-sensitive</em> and uses the <code>Locale</code>
* to tailor information for the user. For example, displaying a number
* is a locale-sensitive operation&mdash; the number should be formatted
* according to the customs and conventions of the user's native country,
* region, or culture.
*
* <p> The {@code Locale} class implements IETF BCP 47 which is composed of
* <a href="http://tools.ietf.org/html/rfc4647">RFC 4647 "Matching of Language
* Tags"</a> and <a href="http://tools.ietf.org/html/rfc5646">RFC 5646 "Tags
* for Identifying Languages"</a> with support for the LDML (UTS#35, "Unicode
* Locale Data Markup Language") BCP 47-compatible extensions for locale data
* exchange.
*
* <p> A <code>Locale</code> object logically consists of the fields
* described below.
*
* <dl>
* <dt><a id="def_language"><b>language</b></a></dt>
*
* <dd>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
* <code>Locale</code> always canonicalizes to lower case.</dd>
*
* <dd>Well-formed language values have the form
* <code>[a-zA-Z]{2,8}</code>. 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.</dd>
*
* <dd>Example: "en" (English), "ja" (Japanese), "kok" (Konkani)</dd>
*
* <dt><a id="def_script"><b>script</b></a></dt>
*
* <dd>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
* <code>Locale</code> always canonicalizes to title case (the first
* letter is upper case and the rest of the letters are lower
* case).</dd>
*
* <dd>Well-formed script values have the form
* <code>[a-zA-Z]{4}</code></dd>
*
* <dd>Example: "Latn" (Latin), "Cyrl" (Cyrillic)</dd>
*
* <dt><a id="def_region"><b>country (region)</b></a></dt>
*
* <dd>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
* <code>Locale</code> always canonicalizes to upper case.</dd>
*
* <dd>Well-formed country/region values have
* the form <code>[a-zA-Z]{2} | [0-9]{3}</code></dd>
*
* <dd>Example: "US" (United States), "FR" (France), "029"
* (Caribbean)</dd>
*
* <dt><a id="def_variant"><b>variant</b></a></dt>
*
* <dd>Any arbitrary value used to indicate a variation of a
* <code>Locale</code>. 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.</dd>
*
* <dd>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").
*
* <p>However, the variant field in <code>Locale</code> 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.</dd>
*
* <dd>Well-formed variant values have the form <code>SUBTAG
* (('_'|'-') SUBTAG)*</code> where <code>SUBTAG =
* [0-9][0-9a-zA-Z]{3} | [0-9a-zA-Z]{5,8}</code>. (Note: BCP 47 only
* uses hyphen ('-') as a delimiter, this is more lenient).</dd>
*
* <dd>Example: "polyton" (Polytonic Greek), "POSIX"</dd>
*
* <dt><a id="def_extensions"><b>extensions</b></a></dt>
*
* <dd>A map from single character keys to string values, indicating
* extensions apart from language identification. The extensions in
* <code>Locale</code> implement the semantics and syntax of BCP 47
* extension subtags and private use subtags. The extensions are
* case insensitive, but <code>Locale</code> canonicalizes all
* extension keys and values to lower case. Note that extensions
* cannot have empty values.</dd>
*
* <dd>Well-formed keys are single characters from the set
* <code>[0-9a-zA-Z]</code>. Well-formed values have the form
* <code>SUBTAG ('-' SUBTAG)*</code> where for the key 'x'
* <code>SUBTAG = [0-9a-zA-Z]{1,8}</code> and for other keys
* <code>SUBTAG = [0-9a-zA-Z]{2,8}</code> (that is, 'x' allows
* single-character subtags).</dd>
*
* <dd>Example: key="u"/value="ca-japanese" (Japanese Calendar),
* key="x"/value="java-1-7"</dd>
* </dl>
*
* <b>Note:</b> Although BCP 47 requires field values to be registered
* in the IANA Language Subtag Registry, the <code>Locale</code> class
* does not provide any validation features. The <code>Builder</code>
* 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.
*
* <h3><a id="def_locale_extension">Unicode locale/language extension</a></h3>
*
* <p>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").
*
* <p>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".
*
* <p>Thus, when a <code>Locale</code> object contains Unicode locale
* attributes and keywords,
* <code>getExtension(UNICODE_LOCALE_EXTENSION)</code> will return a
* String representing this information, for example, "nu-thai". The
* <code>Locale</code> 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)
*
* <p>A well-formed locale key has the form
* <code>[0-9a-zA-Z]{2}</code>. A well-formed locale type has the
* form <code>"" | [0-9a-zA-Z]{3,8} ('-' [0-9a-zA-Z]{3,8})*</code> (it
* can be empty, or a series of subtags 3-8 alphanums in length). A
* well-formed locale attribute has the form
* <code>[0-9a-zA-Z]{3,8}</code> (it is a single subtag with the same
* form as a locale type subtag).
*
* <p>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.
*
* <h4>Creating a Locale</h4>
*
* <p>There are several different ways to create a <code>Locale</code>
* object.
*
* <h5>Builder</h5>
*
* <p>Using {@link Builder} you can construct a <code>Locale</code> object
* that conforms to BCP 47 syntax.
*
* <h5>Constructors</h5>
*
* <p>The <code>Locale</code> class provides three constructors:
* <blockquote>
* <pre>
* {@link #Locale(String language)}
* {@link #Locale(String language, String country)}
* {@link #Locale(String language, String country, String variant)}
* </pre>
* </blockquote>
* These constructors allow you to create a <code>Locale</code> object
* with language, country and variant, but you cannot specify
* script or extensions.
*
* <h5>Factory Methods</h5>
*
* <p>The method {@link #forLanguageTag} creates a <code>Locale</code>
* object for a well-formed BCP 47 language tag.
*
* <h5>Locale Constants</h5>
*
* <p>The <code>Locale</code> class provides a number of convenient constants
* that you can use to create <code>Locale</code> objects for commonly used
* locales. For example, the following creates a <code>Locale</code> object
* for the United States:
* <blockquote>
* <pre>
* Locale.US
* </pre>
* </blockquote>
*
* <h4><a id="LocaleMatching">Locale Matching</a></h4>
*
* <p>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.
*
* <p>In order to do matching a user's preferred locales to a set of language
* tags, <a href="http://tools.ietf.org/html/rfc4647">RFC 4647 Matching of
* Language Tags</a> defines two mechanisms: filtering and lookup.
* <em>Filtering</em> is used to get all matching locales, whereas
* <em>lookup</em> is to choose the best matching locale.
* Matching is done case-insensitively. These matching mechanisms are described
* in the following sections.
*
* <p>A user's preference is called a <em>Language Priority List</em> 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.
*
* <h5>Filtering</h5>
*
* <p>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."
*
* <p>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.
*
* <h5>Lookup</h5>
*
* <p>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."
*
* <p>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.
* <blockquote>
* <pre>
* 1. zh-Hant-TW
* 2. zh-Hant
* 3. zh
* 4. en-US
* 5. en
* </pre>
* </blockquote>
* If there is a language tag which matches completely to a language range
* above, the language tag is returned.
*
* <p>{@code "*"} is the special language range, and it is ignored in lookup.
*
* <p>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.
*
* <h4>Use of Locale</h4>
*
* <p>Once you've created a <code>Locale</code> you can query it for information
* about itself. Use <code>getCountry</code> to get the country (or region)
* code and <code>getLanguage</code> to get the language code.
* You can use <code>getDisplayCountry</code> to get the
* name of the country suitable for displaying to the user. Similarly,
* you can use <code>getDisplayLanguage</code> to get the name of
* the language suitable for displaying to the user. Interestingly,
* the <code>getDisplayXXX</code> 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.
*
* <p>The Java Platform provides a number of classes that perform locale-sensitive
* operations. For example, the <code>NumberFormat</code> class formats
* numbers, currency, and percentages in a locale-sensitive manner. Classes
* such as <code>NumberFormat</code> have several convenience methods
* for creating a default object of that type. For example, the
* <code>NumberFormat</code> class provides these three convenience methods
* for creating a default <code>NumberFormat</code> object:
* <blockquote>
* <pre>
* NumberFormat.getInstance()
* NumberFormat.getCurrencyInstance()
* NumberFormat.getPercentInstance()
* </pre>
* </blockquote>
* 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:
* <blockquote>
* <pre>
* NumberFormat.getInstance(myLocale)
* NumberFormat.getCurrencyInstance(myLocale)
* NumberFormat.getPercentInstance(myLocale)
* </pre>
* </blockquote>
* A <code>Locale</code> is the mechanism for identifying the kind of object
* (<code>NumberFormat</code>) that you would like to get. The locale is
* <STRONG>just</STRONG> a mechanism for identifying objects,
* <STRONG>not</STRONG> a container for the objects themselves.
*
* <h4>Compatibility</h4>
*
* <p>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
* <code>toString</code> 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.
*
* <p>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 <code>toLanguageTag</code> cannot
* represent the state of locales whose language, country, or variant
* do not conform to BCP 47.
*
* <p>Because of these issues, it is recommended that clients migrate
* away from constructing non-conforming locales and use the
* <code>forLanguageTag</code> and <code>Locale.Builder</code> APIs instead.
* Clients desiring a string representation of the complete locale can
* then always rely on <code>toLanguageTag</code> for this purpose.
*
* <h5><a id="special_cases_constructor">Special cases</a></h5>
*
* <p>For compatibility reasons, two
* non-conforming locales are treated as special cases. These are
* <b>{@code ja_JP_JP}</b> and <b>{@code th_TH_TH}</b>. 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.
*
* <p>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.
*
* <p>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.
*
* <h5>Serialization</h5>
*
* <p>During serialization, writeObject writes all fields to the output
* stream, including extensions.
*
* <p>During deserialization, readResolve adds extensions as described
* in <a href="#special_cases_constructor">Special Cases</a>, only
* for the two cases th_TH_TH and ja_JP_JP.
*
* <h5>Legacy language codes</h5>
*
* <p>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.
*
* <p>The APIs added in 1.7 map between the old and new language codes,
* maintaining the old codes internal to Locale (so that
* <code>getLanguage</code> and <code>toString</code> reflect the old
* code), but using the new codes in the BCP 47 language tag APIs (so
* that <code>toLanguageTag</code> 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}.
*
* <h5>Three-letter language/country(region) codes</h5>
*
* <p>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<String> 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<String> createCountryCodeSet() {
return LocaleISOData.computeISO3166_1Alpha3Countries();
}
},
/**
* PART3 is used to represent the ISO3166-3 four letter country codes.
*/
PART3 {
@Override
Set<String> 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<String> createCountryCodeSet();
/**
* Map to hold country codes for each ISO3166 part.
*/
private static Map<IsoCountryCode, Set<String>> iso3166CodesMap = new ConcurrentHashMap<>();
/**
* This method is called from Locale class to retrieve country code set
* for getISOCountries(type)
*/
static Set<String> 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 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.
* <p>
* <b>Note:</b>
* <ul>
* <li>ISO 639 is not a stable standard; some of the language codes it defines
* (specifically "iw", "ji", and "in") have changed. This constructor accepts both the
* old codes ("iw", "ji", and "in") and the new codes ("he", "yi", and "id"), but all other
* API on Locale will return only the OLD codes.
* <li>For backward compatibility reasons, this constructor does not make
* any syntactic checks on the input.
* <li>The two cases ("ja", "JP", "JP") and ("th", "TH", "TH") are handled specially,
* see <a href="#special_cases_constructor">Special Cases</a> for more information.
* </ul>
*
* @param language An ISO 639 alpha-2 or alpha-3 language code, or a language subtag
* up to 8 characters in length. See the <code>Locale</code> 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 <code>Locale</code> class description about valid country values.
* @param variant Any arbitrary value used to indicate a variation of a <code>Locale</code>.
* See the <code>Locale</code> 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.
* <p>
* <b>Note:</b>
* <ul>
* <li>ISO 639 is not a stable standard; some of the language codes it defines
* (specifically "iw", "ji", and "in") have changed. This constructor accepts both the
* old codes ("iw", "ji", and "in") and the new codes ("he", "yi", and "id"), but all other
* API on Locale will return only the OLD codes.
* <li>For backward compatibility reasons, this constructor does not make
* any syntactic checks on the input.
* </ul>
*
* @param language An ISO 639 alpha-2 or alpha-3 language code, or a language subtag
* up to 8 characters in length. See the <code>Locale</code> 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 <code>Locale</code> 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.
* <p>
* <b>Note:</b>
* <ul>
* <li>ISO 639 is not a stable standard; some of the language codes it defines
* (specifically "iw", "ji", and "in") have changed. This constructor accepts both the
* old codes ("iw", "ji", and "in") and the new codes ("he", "yi", and "id"), but all other
* API on Locale will return only the OLD codes.
* <li>For backward compatibility reasons, this constructor does not make
* any syntactic checks on the input.
* </ul>
*
* @param language An ISO 639 alpha-2 or alpha-3 language code, or a language subtag
* up to 8 characters in length. See the <code>Locale</code> 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 <code>Locale</code> constructed from the given
* <code>language</code>, <code>country</code> and
* <code>variant</code>. If the same <code>Locale</code> instance
* is available in the cache, then that instance is
* returned. Otherwise, a new <code>Locale</code> 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 <code>Locale</code> 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) {
LocaleKey key = new LocaleKey(baseloc, extensions);
return LOCALECACHE.get(key);
}
private static class Cache extends LocaleObjectCache<LocaleKey, Locale> {
private Cache() {
}
@Override
protected Locale createObject(LocaleKey key) {
return new Locale(key.base, key.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.
* <p>
* 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.
* <p>
* 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, 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()),
null);
}
/**
* Sets the default locale for this instance of the Java Virtual Machine.
* This does not affect the host locale.
* <p>
* If there is a security manager, its <code>checkPermission</code>
* method is called with a <code>PropertyPermission("user.language", "write")</code>
* permission before the default locale is changed.
* <p>
* 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.
* <p>
* 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.
* <p>
* 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
* <code>checkPermission</code> method doesn't allow the operation.
* @throws NullPointerException if <code>newLocale</code> 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.
* <p>
* If there is a security manager, its checkPermission method is called
* with a PropertyPermission("user.language", "write") permission before
* the default locale is changed.
* <p>
* 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.
* <p>
* 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 <code>Locale</code>
* 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}.
* <p>
* <b>Note:</b> The <code>Locale</code> 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.
* <p>
* 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<String> 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.
* <p>
* <b>Note:</b>
* <ul>
* <li>ISO 639 is not a stable standard&mdash; some languages' codes have changed.
* The list this function returns includes both the new and the old codes for the
* languages whose codes have changed.
* <li>The <code>Locale</code> class also supports language codes up to
* 8 characters in length. Therefore, the list returned by this method does
* not contain ALL valid codes that can be used to create Locales.
* </ul>
*
* @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.
*
* <p><b>Note:</b> ISO 639 is not a stable standard&mdash; 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
* <pre>
* if (locale.getLanguage().equals("he")) // BAD!
* ...
* </pre>
* Instead, do
* <pre>
* if (locale.getLanguage().equals(new Locale("he").getLanguage()))
* ...
* </pre>
* @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 <a href="#def_extensions">
* extensions</a>.
*
* @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 <a href="#def_extensions">
* extensions</a>. 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 <code>[0-9A-Za-z]</code>. 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<Character> 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<String> 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 <code>key</code> 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<String> 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 <code>Locale</code>
* object, consisting of language, country, variant, script,
* and extensions as below:
* <blockquote>
* language + "_" + country + "_" + (variant + "_#" | "#") + script + "_" + extensions
* </blockquote>
*
* 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}.
*
* <p>When the locale has neither script nor extensions, the result is the same as in
* Java 6 and prior.
*
* <p>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).
*
* <p>If script or extensions are present and variant is missing, no underscore is
* added before the "#".
*
* <p>This behavior is designed to support debugging and to be compatible with
* previous uses of <code>toString</code> that expected language, country, and variant
* fields only. To represent a Locale as a String for interchange purposes, use
* {@link #toLanguageTag}.
*
* <p>Examples: <ul>
* <li>{@code en}</li>
* <li>{@code de_DE}</li>
* <li>{@code _GB}</li>
* <li>{@code en_US_WIN}</li>
* <li>{@code de__POSIX}</li>
* <li>{@code zh_CN_#Hans}</li>
* <li>{@code zh_TW_#Hant_x-java}</li>
* <li>{@code th_TH_TH_#u-nu-thai}</li></ul>
*
* @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.
*
* <p>If this <code>Locale</code> 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:
*
* <p><b>Language:</b> If language is empty, or not <a
* href="#def_language" >well-formed</a> (for example "a" or
* "e2"), it will be emitted as "und" (Undetermined).
*
* <p><b>Country:</b> If country is not <a
* href="#def_region">well-formed</a> (for example "12" or "USA"),
* it will be omitted.
*
* <p><b>Variant:</b> If variant <b>is</b> <a
* href="#def_variant">well-formed</a>, each sub-segment
* (delimited by '-' or '_') is emitted as a subtag. Otherwise:
* <ul>
*
* <li>if all sub-segments match <code>[0-9a-zA-Z]{1,8}</code>
* (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".
*
* <li>if any sub-segment does not match
* <code>[0-9a-zA-Z]{1,8}</code>, 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".</li></ul>
*
* <p><b>Special Conversions:</b> Java supports some old locale
* representations, including deprecated ISO language codes,
* for compatibility. This method performs the following
* conversions:
* <ul>
*
* <li>Deprecated ISO language codes "iw", "ji", and "in" are
* converted to "he", "yi", and "id", respectively.
*
* <li>A locale with language "no", country "NO", and variant
* "NY", representing Norwegian Nynorsk (Norway), is converted
* to a language tag "nn-NO".</li></ul>
*
* <p><b>Note:</b> 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,
* <pre>
* new Locale("xx", "YY").toLanguageTag();</pre>
*
* 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));
}
List<String>subtags = 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.
*
* <p>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.
*
* <p>The following <b>conversions</b> are performed:<ul>
*
* <li>The language code "und" is mapped to language "".
*
* <li>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.)
*
* <li>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:
*
* <pre>
* 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"
* </pre>
*
* <li>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:
*
* <pre>
* Locale.forLanguageTag("ar-aao").getLanguage(); // returns "aao"
* Locale.forLanguageTag("en-abc-def-us").toString(); // returns "abc_US"
* </pre>
*
* <li>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.
*
* <li>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:
*
* <pre>
* 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"
* </pre></ul>
*
* <p>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.
*
* <p>Grandfathered tags with canonical replacements are as follows:
*
* <table class="striped">
* <caption style="display:none">Grandfathered tags with canonical replacements</caption>
* <thead style="text-align:center">
* <tr><th style="padding: 0 2px">grandfathered tag</th><th style="padding: 0 2px">modern replacement</th></tr>
* </thead>
* <tbody style="text-align:center">
* <tr><td>art-lojban</td><td>jbo</td></tr>
* <tr><td>i-ami</td><td>ami</td></tr>
* <tr><td>i-bnn</td><td>bnn</td></tr>
* <tr><td>i-hak</td><td>hak</td></tr>
* <tr><td>i-klingon</td><td>tlh</td></tr>
* <tr><td>i-lux</td><td>lb</td></tr>
* <tr><td>i-navajo</td><td>nv</td></tr>
* <tr><td>i-pwn</td><td>pwn</td></tr>
* <tr><td>i-tao</td><td>tao</td></tr>
* <tr><td>i-tay</td><td>tay</td></tr>
* <tr><td>i-tsu</td><td>tsu</td></tr>
* <tr><td>no-bok</td><td>nb</td></tr>
* <tr><td>no-nyn</td><td>nn</td></tr>
* <tr><td>sgn-BE-FR</td><td>sfb</td></tr>
* <tr><td>sgn-BE-NL</td><td>vgt</td></tr>
* <tr><td>sgn-CH-DE</td><td>sgg</td></tr>
* <tr><td>zh-guoyu</td><td>cmn</td></tr>
* <tr><td>zh-hakka</td><td>hak</td></tr>
* <tr><td>zh-min-nan</td><td>nan</td></tr>
* <tr><td>zh-xiang</td><td>hsn</td></tr>
* </tbody>
* </table>
*
* <p>Grandfathered tags with no modern replacement will be
* converted as follows:
*
* <table class="striped">
* <caption style="display:none">Grandfathered tags with no modern replacement</caption>
* <thead style="text-align:center">
* <tr><th style="padding: 0 2px">grandfathered tag</th><th style="padding: 0 2px">converts to</th></tr>
* </thead>
* <tbody style="text-align:center">
* <tr><td>cel-gaulish</td><td>xtg-x-cel-gaulish</td></tr>
* <tr><td>en-GB-oed</td><td>en-GB-x-oed</td></tr>
* <tr><td>i-default</td><td>en-x-i-default</td></tr>
* <tr><td>i-enochian</td><td>und-x-i-enochian</td></tr>
* <tr><td>i-mingo</td><td>see-x-i-mingo</td></tr>
* <tr><td>zh-min</td><td>nan-x-zh-min</td></tr>
* </tbody>
* </table>
*
* <p>For a list of all grandfathered tags, see the
* IANA Language Subtag Registry (search for "Type: grandfathered").
*
* <p><b>Note</b>: there is no guarantee that <code>toLanguageTag</code>
* and <code>forLanguageTag</code> will round-trip.
*
* @param languageTag the language tag
* @return The locale that best represents the language tag.
* @throws NullPointerException if <code>languageTag</code> is <code>null</code>
* @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.
*
* <p>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 <code>inLocale</code> is <code>null</code>
*/
public String getDisplayLanguage(Locale inLocale) {
return getDisplayString(baseLocale.getLanguage(), 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 <code>inLocale</code> is <code>null</code>
* @since 1.7
*/
public String getDisplayScript(Locale inLocale) {
return getDisplayString(baseLocale.getScript(), 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 <code>inLocale</code> is <code>null</code>
*/
public String getDisplayCountry(Locale inLocale) {
return getDisplayString(baseLocale.getRegion(), inLocale, DISPLAY_COUNTRY);
}
private String getDisplayString(String code, Locale inLocale, int type) {
if (code.length() == 0) {
return "";
}
if (inLocale == null) {
throw new NullPointerException();
}
LocaleServiceProviderPool pool =
LocaleServiceProviderPool.getPool(LocaleNameProvider.class);
String key = (type == DISPLAY_VARIANT ? "%%"+code : code);
String result = pool.getLocalizedObject(
LocaleNameGetter.INSTANCE,
inLocale, key, type, code);
if (result != null) {
return result;
}
return 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 <code>inLocale</code> is <code>null</code>
*/
public String getDisplayVariant(Locale inLocale) {
if (baseLocale.getVariant().length() == 0)
return "";
LocaleResources lr = LocaleProviderAdapter.forJRE().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("ListPattern"),
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(), and getDisplayVariant() assembled
* into a single string. The the non-empty values are used in order,
* with the second and subsequent names in parentheses. For example:
* <blockquote>
* language (script, country, variant)<br>
* language (country)<br>
* language (variant)<br>
* script (country)<br>
* country<br>
* </blockquote>
* depending on which fields are specified in 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(),
* and getDisplayVariant() assembled into a single string.
* The non-empty values are used in order,
* with the second and subsequent names in parentheses. For example:
* <blockquote>
* language (script, country, variant)<br>
* language (country)<br>
* language (variant)<br>
* script (country)<br>
* country<br>
* </blockquote>
* depending on which fields are specified in 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 <code>inLocale</code> is <code>null</code>
*/
public String getDisplayName(Locale inLocale) {
LocaleResources lr = LocaleProviderAdapter.forJRE().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 listPattern = lr.getLocaleName("ListPattern");
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, listPattern, listCompositionPattern);
}
}
ArrayList<String> 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));
}
// 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, listPattern, 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<names.length; ++i) {
names[i] = getDisplayString(tokenizer.nextToken(),
inLocale, DISPLAY_VARIANT);
}
return names;
}
/**
* 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.
* @param listPattern should create a MessageFormat taking 0-3 arguments
* and formatting them into a list.
* @param listCompositionPattern should take 2 arguments
* and is used by composeList.
* @return a string representing the list.
*/
private static String formatList(String[] stringList, String listPattern, String listCompositionPattern) {
// If we have no list patterns, compose the list in a simple,
// non-localized way.
if (listPattern == null || listCompositionPattern == null) {
StringJoiner sj = new StringJoiner(",");
for (int i = 0; i < stringList.length; ++i) {
sj.add(stringList[i]);
}
return sj.toString();
}
// Compose the list down to three elements if necessary
if (stringList.length > 3) {
MessageFormat format = new MessageFormat(listCompositionPattern);
stringList = composeList(format, stringList);
}
// Rebuild the argument list with the list length as the first element
Object[] args = new Object[stringList.length + 1];
System.arraycopy(stringList, 0, args, 1, stringList.length);
args[0] = stringList.length;
// Format it using the pattern in the resource
MessageFormat format = new MessageFormat(listPattern);
return format.format(args);
}
/**
* Given a list of strings, return a list shortened to three elements.
* Shorten it by applying the given format to the first two elements
* recursively.
* @param format a format which takes two arguments
* @param list a list of strings
* @return if the list is three elements or shorter, the same list;
* otherwise, a new list of three elements.
*/
private static String[] composeList(MessageFormat format, String[] list) {
if (list.length <= 3) return list;
// Use the given format to compose the first two elements into one
String[] listItems = { list[0], list[1] };
String newItem = format.format(listItems);
// Form a new list one element shorter
String[] newList = new String[list.length-1];
System.arraycopy(list, 2, newList, 1, newList.length-1);
newList[0] = newItem;
// Recurse
return composeList(format, newList);
}
// 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 <a href="java/util/Locale.html#getLanguage()">getLanguage()</a>)
* @serialField country String
* country subtag in upper case. (See <a href="java/util/Locale.html#getCountry()">getCountry()</a>)
* @serialField variant String
* variant subtags separated by LOWLINE characters. (See <a href="java/util/Locale.html#getVariant()">getVariant()</a>)
* @serialField hashcode int
* deprecated, for forward compatibility only
* @serialField script String
* script subtag in title case (See <a href="java/util/Locale.html#getScript()">getScript()</a>)
* @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 <a href="java/util/Locale.html#getExtensionKeys()">getExtensionKeys()</a>,
* <a href="java/util/Locale.html#getExtension(char)">getExtension(char)</a>)
*/
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 <code>Locale</code> to the specified <code>ObjectOutputStream</code>.
* @param out the <code>ObjectOutputStream</code> 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 <code>Locale</code>.
* @param in the <code>ObjectInputStream</code> 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 <code>Locale</code> instance equivalent to
* the deserialized <code>Locale</code>. 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 <code>UNICODE_LOCALE_EXTENSION</code>
* "ca"/"japanese" (calendar type is "japanese") or "nu"/"thai" (number script
* type is "thai"). See <a href="Locale.html#special_cases_constructor">Special Cases</a>
* for more information.
*
* @return an instance of <code>Locale</code> equivalent to
* the deserialized <code>Locale</code>.
* @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<LocaleNameProvider, String> {
private static final LocaleNameGetter INSTANCE = new LocaleNameGetter();
@Override
public String getObject(LocaleNameProvider localeNameProvider,
Locale locale,
String key,
Object... params) {
assert params.length == 2;
int type = (Integer)params[0];
String code = (String)params[1];
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);
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"),
/**
* 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");
Category(String languageKey, String scriptKey, String countryKey, String variantKey) {
this.languageKey = languageKey;
this.scriptKey = scriptKey;
this.countryKey = countryKey;
this.variantKey = variantKey;
}
final String languageKey;
final String scriptKey;
final String countryKey;
final String variantKey;
}
/**
* <code>Builder</code> is used to build instances of <code>Locale</code>
* from values configured by the setters. Unlike the <code>Locale</code>
* constructors, the <code>Builder</code> checks if a value configured by a
* setter satisfies the syntax requirements defined by the <code>Locale</code>
* class. A <code>Locale</code> object created by a <code>Builder</code> is
* well-formed and can be transformed to a well-formed IETF BCP 47 language tag
* without losing information.
*
* <p><b>Note:</b> The <code>Locale</code> 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 <code>setVariant</code> throws
* <code>IllformedLocaleException</code> 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 <code>Locale</code>
* object created this way might lose the variant information when
* transformed to a BCP 47 language tag.
*
* <p>The following example shows how to create a <code>Locale</code> object
* with the <code>Builder</code>.
* <blockquote>
* <pre>
* Locale aLocale = new Builder().setLanguage("sr").setScript("Latn").setRegion("RS").build();
* </pre>
* </blockquote>
*
* <p>Builders can be reused; <code>clear()</code> 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 <code>Builder</code> to match the provided
* <code>locale</code>. Existing state is discarded.
*
* <p>All fields of the locale must be well-formed, see {@link Locale}.
*
* <p>Locales with any ill-formed fields cause
* <code>IllformedLocaleException</code> to be thrown, except for the
* following three cases which are accepted for compatibility
* reasons:<ul>
* <li>Locale("ja", "JP", "JP") is treated as "ja-JP-u-ca-japanese"
* <li>Locale("th", "TH", "TH") is treated as "th-TH-u-nu-thai"
* <li>Locale("no", "NO", "NY") is treated as "nn-NO"</ul>
*
* @param locale the locale
* @return This builder.
* @throws IllformedLocaleException if <code>locale</code> has
* any ill-formed fields.
* @throws NullPointerException if <code>locale</code> 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 <code>Locale.forLanguageTag</code>, which
* just discards ill-formed and following portions of the
* tag).
*
* @param languageTag the language tag
* @return This builder.
* @throws IllformedLocaleException if <code>languageTag</code> 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 <code>language</code> is the empty string or
* null, the language in this <code>Builder</code> is removed. Otherwise,
* the language must be <a href="./Locale.html#def_language">well-formed</a>
* or an exception is thrown.
*
* <p>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 <code>language</code> 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 <code>script</code> is null or the empty string,
* the script in this <code>Builder</code> is removed.
* Otherwise, the script must be <a href="./Locale.html#def_script">well-formed</a> or an
* exception is thrown.
*
* <p>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 <code>script</code> 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 <code>Builder</code> is removed. Otherwise,
* the region must be <a href="./Locale.html#def_region">well-formed</a> or an
* exception is thrown.
*
* <p>The typical region value is a two-letter ISO 3166 code or a
* three-digit UN M.49 area code.
*
* <p>The country value in the <code>Locale</code> created by the
* <code>Builder</code> is always normalized to upper case.
*
* @param region the region
* @return This builder.
* @throws IllformedLocaleException if <code>region</code> 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 <code>Builder</code> is removed. Otherwise, it
* must consist of one or more <a href="./Locale.html#def_variant">well-formed</a>
* subtags, or an exception is thrown.
*
* <p><b>Note:</b> This method checks if <code>variant</code>
* satisfies the IETF BCP 47 variant subtag's syntax requirements,
* and normalizes the value to lowercase letters. However,
* the <code>Locale</code> class does not impose any syntactic
* restriction on variant, and the variant value in
* <code>Locale</code> is case sensitive. To set such a variant,
* use a Locale constructor.
*
* @param variant the variant
* @return This builder.
* @throws IllformedLocaleException if <code>variant</code> 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 <a href="./Locale.html#def_extensions">well-formed</a> or an exception
* is thrown.
*
* <p><b>Note:</b> 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.
*
* <p><b>Note:</b> 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 <code>key</code> is illegal
* or <code>value</code> 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 <a
* href="./Locale.html#def_locale_extension">well-formed</a> or an exception
* is thrown.
*
* <p>Keys and types are converted to lower case.
*
* <p><b>Note</b>: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 <code>key</code> or <code>type</code>
* is ill-formed
* @throws NullPointerException if <code>key</code> 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 <a
* href="./Locale.html#def_locale_extension">well-formed</a> or an exception
* is thrown.
*
* @param attribute the attribute
* @return This builder.
* @throws NullPointerException if <code>attribute</code> is null
* @throws IllformedLocaleException if <code>attribute</code> 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 <a
* href="./Locale.html#def_locale_extension">well-formed</a> or an exception
* is thrown.
*
* <p>Attribute comparison for removal is case-insensitive.
*
* @param attribute the attribute
* @return This builder.
* @throws NullPointerException if <code>attribute</code> is null
* @throws IllformedLocaleException if <code>attribute</code> is ill-formed
* @see #setExtension(char, String)
*/
public Builder removeUnicodeLocaleAttribute(String 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 <code>Locale</code> created from the fields set
* on this builder.
*
* <p>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 <a href="http://tools.ietf.org/html/rfc4647">RFC 4647
* Matching of Language Tags</a> for details.
*
* <p>As an example, think of two Language Priority Lists each of which
* includes only one language range and a set of following language tags:
*
* <pre>
* 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)
* </pre>
*
* The filtering method will behave as follows:
*
* <table class="striped">
* <caption>Filtering method behavior</caption>
* <thead>
* <tr>
* <th>Filtering Mode</th>
* <th>Language Priority List: {@code "de-DE"}</th>
* <th>Language Priority List: {@code "de-*-DE"}</th>
* </tr>
* </thead>
* <tbody>
* <tr>
* <td style="vertical-align:top">
* {@link FilteringMode#AUTOSELECT_FILTERING AUTOSELECT_FILTERING}
* </td>
* <td style="vertical-align:top">
* Performs <em>basic</em> filtering and returns {@code "de-DE"} and
* {@code "de-DE-1996"}.
* </td>
* <td style="vertical-align:top">
* Performs <em>extended</em> filtering and returns {@code "de-DE"},
* {@code "de-Deva-DE"}, {@code "de-DE-1996"}, {@code "de-Latn-DE"}, and
* {@code "de-Latn-DE-1996"}.
* </td>
* </tr>
* <tr>
* <td style="vertical-align:top">
* {@link FilteringMode#EXTENDED_FILTERING EXTENDED_FILTERING}
* </td>
* <td style="vertical-align:top">
* Performs <em>extended</em> filtering and returns {@code "de-DE"},
* {@code "de-Deva-DE"}, {@code "de-DE-1996"}, {@code "de-Latn-DE"}, and
* {@code "de-Latn-DE-1996"}.
* </td>
* <td style="vertical-align:top">Same as above.</td>
* </tr>
* <tr>
* <td style="vertical-align:top">
* {@link FilteringMode#IGNORE_EXTENDED_RANGES IGNORE_EXTENDED_RANGES}
* </td>
* <td style="vertical-align:top">
* Performs <em>basic</em> filtering and returns {@code "de-DE"} and
* {@code "de-DE-1996"}.
* </td>
* <td style="vertical-align:top">
* Performs <em>basic</em> filtering and returns {@code null} because
* nothing matches.
* </td>
* </tr>
* <tr>
* <td style="vertical-align:top">
* {@link FilteringMode#MAP_EXTENDED_RANGES MAP_EXTENDED_RANGES}
* </td>
* <td style="vertical-align:top">Same as above.</td>
* <td style="vertical-align:top">
* Performs <em>basic</em> filtering and returns {@code "de-DE"} and
* {@code "de-DE-1996"} because {@code "de-*-DE"} is mapped to
* {@code "de-DE"}.
* </td>
* </tr>
* <tr>
* <td style="vertical-align:top">
* {@link FilteringMode#REJECT_EXTENDED_RANGES REJECT_EXTENDED_RANGES}
* </td>
* <td style="vertical-align:top">Same as above.</td>
* <td style="vertical-align:top">
* Throws {@link IllegalArgumentException} because {@code "de-*-DE"} is
* not a valid basic language range.
* </td>
* </tr>
* </tbody>
* </table>
*
* @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 <em>Language Range</em> defined in
* <a href="http://tools.ietf.org/html/rfc4647">RFC 4647 Matching of
* Language Tags</a>. A language range is an identifier which is used to
* select language tag(s) meeting specific requirements by using the
* mechanisms described in <a href="Locale.html#LocaleMatching">Locale
* Matching</a>. A list which represents a user's preferences and consists
* of language ranges is called a <em>Language Priority List</em>.
*
* <p>There are two types of language ranges: basic and extended. In RFC
* 4647, the syntax of language ranges is expressed in
* <a href="http://tools.ietf.org/html/rfc4234">ABNF</a> as follows:
* <blockquote>
* <pre>
* basic-language-range = (1*8ALPHA *("-" 1*8alphanum)) / "*"
* extended-language-range = (1*8ALPHA / "*")
* *("-" (1*8alphanum / "*"))
* alphanum = ALPHA / DIGIT
* </pre>
* </blockquote>
* 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.
*
* <p>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.
*
* <p>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.
*
* <p>The {@code ranges} to be given can take one of the following
* forms:
*
* <pre>
* "Accept-Language: ja,en;q=0.4" (weighted list with Accept-Language prefix)
* "ja,en;q=0.4" (weighted list)
* "ja,en" (prioritized list)
* </pre>
*
* In a weighted list, each language range is given a weight value.
* The weight value is identical to the "quality value" in
* <a href="http://tools.ietf.org/html/rfc2616">RFC 2616</a>, 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.
*
* <p>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.
*
* <p>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.
*
* <p>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:
*
* <pre>
* <b>Range</b> <b>Weight</b>
* "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
* </pre>
*
* 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 <a href="http://tools.ietf.org/html/rfc2616">RFC
* 2616</a>
* @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<LanguageRange> 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 <a href="http://tools.ietf.org/html/rfc2616">RFC
* 2616</a>
* @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<LanguageRange> parse(String ranges,
Map<String, List<String>> 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}.
*
* <p>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.
*
* <pre>
* An example of map:
* <b>Key</b> <b>Value</b>
* "zh" (Chinese) "zh",
* "zh-Hans"(Simplified Chinese)
* "zh-HK" (Chinese, Hong Kong) "zh-HK"
* "zh-TW" (Chinese, Taiwan) "zh-TW"
* </pre>
*
* The customization is performed after modification using the IANA
* Language Subtag Registry.
*
* <p>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"}.
*
* <p>{@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.
*
* <p>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<LanguageRange> mapEquivalents(
List<LanguageRange>priorityList,
Map<String, List<String>> 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.
*
* @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<Locale> filter(List<LanguageRange> priorityList,
Collection<Locale> 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}.
*
* @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<Locale> filter(List<LanguageRange> priorityList,
Collection<Locale> locales) {
return filter(priorityList, locales, FilteringMode.AUTOSELECT_FILTERING);
}
/**
* Returns a list of matching languages tags using the basic filtering
* 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 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<String> filterTags(List<LanguageRange> priorityList,
Collection<String> 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}.
*
* @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<String> filterTags(List<LanguageRange> priorityList,
Collection<String> 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 <code>Locale</code> 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<LanguageRange> priorityList,
Collection<Locale> locales) {
return LocaleMatcher.lookup(priorityList, locales);
}
/**
* Returns 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 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<LanguageRange> priorityList,
Collection<String> tags) {
return LocaleMatcher.lookupTag(priorityList, tags);
}
}