java.util
Class Locale

java.lang.Object
  |
  +--java.util.Locale

public final class Locale

extends Object

implements Cloneable, Serializable

A Locale object represents a specific geographical, political, or cultural region. An operation that requires a Locale to perform its task is called locale-sensitive and uses the Locale to tailor information for the user. For example, displaying a number is a locale-sensitive operation--the number should be formatted according to the customs/conventions of the user's native country, region, or culture.

You create a Locale object using one of the two constructors in this class:

 Locale(String language, String country)
 Locale(String language, String country, String variant)
 

The first argument to both constructors is a valid ISO Language Code. These codes are the lower-case two-letter codes as defined by ISO-639. You can find a full list of these codes at a number of sites, such as:
http://www.ics.uci.edu/pub/ietf/http/related/iso639.txt

The second argument to both constructors is a valid ISO Country Code. These codes are the upper-case two-letter codes as defined by ISO-3166. You can find a full list of these codes at a number of sites, such as:
http://www.chemie.fu-berlin.de/diverse/doc/ISO_3166.html

The second constructor requires a third argument--the Variant. The Variant codes are vendor and browser-specific. For example, use WIN for Windows, MAC for Macintosh, and POSIX for POSIX. Where there are two variants, separate them with an underscore, and put the most important one first. For example, a Traditional Spanish collation might construct a locale with parameters for language, country and variant as: "es", "ES", "Traditional_WIN".

Because a Locale object is just an identifier for a region, no validity check is performed when you construct a Locale. If you want to see whether particular resources are available for the Locale you construct, you must query those resources. For example, ask the NumberFormat for the locales it supports using its getAvailableLocales method.
Note: When you ask for a resource for a particular locale, you get back the best available match, not necessarily precisely what you asked for. For more information, look at ResourceBundle.

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

 Locale.US
 

Once you've created a Locale you can query it for information about itself. Use getCountry to get the ISO Country Code and getLanguage to get the ISO Language Code. You can use getDisplayCountry to get the name of the country suitable for displaying to the user. Similarly, you can use getDisplayLanguage to get the name of the language suitable for displaying to the user. Interestingly, the getDisplayXXX methods are themselves locale-sensitive and have two versions: one that uses the default locale and one that uses the locale specified as an argument.

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

 NumberFormat.getInstance()
 NumberFormat.getCurrencyInstance()
 NumberFormat.getPercentInstance()
 

These methods have two variants; one with an explicit locale and one without; the latter using the default locale.

 NumberFormat.getInstance(myLocale)
 NumberFormat.getCurrencyInstance(myLocale)
 NumberFormat.getPercentInstance(myLocale)
 

A Locale is the mechanism for identifying the kind of object (NumberFormat) that you would like to get. The locale is just a mechanism for identifying objects, not a container for the objects themselves.

Each class that performs locale-sensitive operations allows you to get all the available objects of that type. You can sift through these objects by language, country, or variant, and use the display names to present a menu to the user. For example, you can create a menu of all the collation objects suitable for a given language. Such classes must implement these three class methods:

 public static Locale[] getAvailableLocales()
 public static String getDisplayName(Locale objectLocale,
                                     Locale displayLocale)
 public static final String getDisplayName(Locale objectLocale)
     // getDisplayName will throw MissingResourceException if the locale
     // is not one of the available locales.
 

See Also:

ResourceBundle, Format, NumberFormat, Collator, Serialized Form

Field Summary

static Locale	CANADA Useful constant for country.
static Locale	CANADA_FRENCH Useful constant for country.
static Locale	CHINA Useful constant for country.
static Locale	CHINESE Useful constant for language.
static Locale	ENGLISH Useful constant for language.
static Locale	FRANCE Useful constant for country.
static Locale	FRENCH Useful constant for language.
static Locale	GERMAN Useful constant for language.
static Locale	GERMANY Useful constant for country.
static Locale	ITALIAN Useful constant for language.
static Locale	ITALY Useful constant for country.
static Locale	JAPAN Useful constant for country.
static Locale	JAPANESE Useful constant for language.
static Locale	KOREA Useful constant for country.
static Locale	KOREAN Useful constant for language.
static Locale	PRC Useful constant for country.
static Locale	SIMPLIFIED_CHINESE Useful constant for language.
static Locale	TAIWAN Useful constant for country.
static Locale	TRADITIONAL_CHINESE Useful constant for language.
static Locale	UK Useful constant for country.
static Locale	US Useful constant for country.

Constructor Summary

Locale(String language, String country)
Construct a locale from language, country.

Locale(String language, String country, String variant)
Construct a locale from language, country, variant.

Method Summary

Object	clone() Overrides Cloneable
boolean	equals(Object obj) Returns true if this Locale is equal to another object.
static Locale[]	getAvailableLocales() Returns a list of all installed locales.
String	getCountry() Returns the country/region code for this locale, which will either be the empty string or an upercase ISO 3166 2-letter code.
static Locale	getDefault() Common method of getting the current default Locale.
String	getDisplayCountry() Returns a name for the locale's country that is appropriate for display to the user.
String	getDisplayCountry(Locale inLocale) Returns a name for the locale's country that is appropriate for display to the user.
String	getDisplayLanguage() Returns a name for the locale's language that is appropriate for display to the user.
String	getDisplayLanguage(Locale inLocale) Returns a name for the locale's language that is appropriate for display to the user.
String	getDisplayName() Returns a name for the locale that is appropriate for display to the user.
String	getDisplayName(Locale inLocale) Returns a name for the locale that is appropriate for display to the user.
String	getDisplayVariant() Returns a name for the locale's variant code that is appropriate for display to the user.
String	getDisplayVariant(Locale inLocale) Returns a name for the locale's variant code that is appropriate for display to the user.
String	getISO3Country() Returns a three-letter abbreviation for this locale's country.
String	getISO3Language() Returns a three-letter abbreviation for this locale's language.
static String[]	getISOCountries() Returns a list of all 2-letter country codes defined in ISO 3166.
static String[]	getISOLanguages() Returns a list of all 2-letter language codes defined in ISO 639.
String	getLanguage() Returns the language code for this locale, which will either be the empty string or a lowercase ISO 639 code.
String	getVariant() Returns the variant code for this locale.
int	hashCode() Override hashCode.
static void	setDefault(Locale newLocale) Sets the default locale for the whole JVM.
String	toString() Getter for the programmatic name of the entire locale, with the language, country and variant separated by underbars.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

ENGLISH

public static final Locale ENGLISH

Useful constant for language.

FRENCH

public static final Locale FRENCH

Useful constant for language.

GERMAN

public static final Locale GERMAN

Useful constant for language.

ITALIAN

public static final Locale ITALIAN

Useful constant for language.

JAPANESE

public static final Locale JAPANESE

Useful constant for language.

KOREAN

public static final Locale KOREAN

Useful constant for language.

CHINESE

public static final Locale CHINESE

Useful constant for language.

SIMPLIFIED_CHINESE

public static final Locale SIMPLIFIED_CHINESE

Useful constant for language.

TRADITIONAL_CHINESE

public static final Locale TRADITIONAL_CHINESE

Useful constant for language.

FRANCE

public static final Locale FRANCE

Useful constant for country.

GERMANY

public static final Locale GERMANY

Useful constant for country.

ITALY

public static final Locale ITALY

Useful constant for country.

JAPAN

public static final Locale JAPAN

Useful constant for country.

KOREA

public static final Locale KOREA

Useful constant for country.

CHINA

public static final Locale CHINA

Useful constant for country.

PRC

public static final Locale PRC

Useful constant for country.

TAIWAN

public static final Locale TAIWAN

Useful constant for country.

UK

public static final Locale UK

Useful constant for country.

US

public static final Locale US

Useful constant for country.

CANADA

public static final Locale CANADA

Useful constant for country.

CANADA_FRENCH

public static final Locale CANADA_FRENCH

Useful constant for country.

Constructor Detail

Locale

public Locale(String language,
              String country,
              String variant)

Construct a locale from language, country, variant. NOTE: 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.

Parameters:

language - lowercase two-letter ISO-639 code.

country - uppercase two-letter ISO-3166 code.

variant - vendor and browser specific code. See class description.

Locale

public Locale(String language,
              String country)

Construct a locale from language, country. NOTE: 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.

Parameters:

language - lowercase two-letter ISO-639 code.

country - uppercase two-letter ISO-3166 code.

Method Detail

getDefault

public static Locale getDefault()

Common method of getting the current default Locale. Used for the presentation: menus, dialogs, etc. Generally set once when your applet or application is initialized, then never reset. (If you do reset the default locale, you probably want to reload your GUI, so that the change is reflected in your interface.)

More advanced programs will allow users to use different locales for different fields, e.g. in a spreadsheet.
Note that the initial setting will match the host system.

setDefault

public static void setDefault(Locale newLocale)

Sets the default locale for the whole JVM. Normally set once at the beginning of an application, then never reset. setDefault does not reset the host locale.

If there is a security manager, its checkPermission method is called with a PropertyPermission("user.language", "write") permission.

Parameters:

newLocale - The new default Locale.

Throws:

SecurityException - if a security manager exists and its checkPermission method doesn't allow the operation.

See Also:

SecurityManager.checkPermission(java.security.Permission), PropertyPermission

getAvailableLocales

public static Locale[] getAvailableLocales()

Returns a list of all installed locales.

getISOCountries

public static String[] getISOCountries()

Returns a list of all 2-letter country codes defined in ISO 3166. Can be used to create Locales.

getISOLanguages

public static String[] getISOLanguages()

Returns a list of all 2-letter language codes defined in ISO 639. Can be used to create Locales. [NOTE: ISO 639 is not a stable standard-- 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.]

getLanguage

public String getLanguage()

Returns the language code for this locale, which will either be the empty string or a lowercase ISO 639 code.

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

 if (locale.getLanguage().equals("he")
    ...
 

Instead, do

 if (locale.getLanguage().equals(new Locale("he", "", "").getLanguage())
    ...

See Also:

getDisplayLanguage()

getCountry

public String getCountry()

Returns the country/region code for this locale, which will either be the empty string or an upercase ISO 3166 2-letter code.

See Also:

getDisplayCountry()

getVariant

public String getVariant()

Returns the variant code for this locale.

See Also:

getDisplayVariant()

toString

public final String toString()

Getter for the programmatic name of the entire locale, with the language, country and variant separated by underbars. Language is always lower case, and country is always upper case. If the language is missing, the string will begin with an underbar. If both the language and country fields are missing, this function will return the empty string, even if the variant field is filled in (you can't have a locale with just a variant-- the variant must accompany a valid language or country code). Examples: "en", "de_DE", "_GB", "en_US_WIN", "de__POSIX", "fr_MAC"

Overrides:

toString in class Object

See Also:

getDisplayName()

getISO3Language

public String getISO3Language()
                       throws MissingResourceException

Returns a three-letter abbreviation for this locale's language. If the locale doesn't specify a language, this will be the empty string. Otherwise, this will be a lowercase ISO 639-2/T language code.

Throws:

MissingResourceException - Throws MissingResourceException if the three-letter language abbreviation is not available for this locale.

getISO3Country

public String getISO3Country()
                      throws MissingResourceException

Returns a three-letter abbreviation for this locale's country. If the locale doesn't specify a country, this will be tbe the empty string. Otherwise, this will be an uppercase ISO 3166 3-letter country code.

Throws:

MissingResourceException - Throws MissingResourceException if the three-letter country abbreviation is not available for this locale.

getDisplayLanguage

public final String getDisplayLanguage()

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 locale. For example, if the locale is fr_FR and the default locale is en_US, getDisplayLanguage() will return "French"; if the locale is en_US and the default locale is fr_FR, getDisplayLanguage() will return "anglais". If the name returned cannot be localized for the default 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.

getDisplayLanguage

public String getDisplayLanguage(Locale inLocale)

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 default locale, 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.

getDisplayCountry

public final String getDisplayCountry()

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 locale. For example, if the locale is fr_FR and the default locale is en_US, getDisplayCountry() will return "France"; if the locale is en_US and the default locale is fr_FR, getDisplayLanguage() will return "Etats-Unis". If the name returned cannot be localized for the default 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.

getDisplayCountry

public String getDisplayCountry(Locale inLocale)

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, getDisplayLanguage() 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 default locale, 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.

getDisplayVariant

public final String getDisplayVariant()

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 locale. If the locale doesn't specify a variant code, this function returns the empty string.

getDisplayVariant

public String getDisplayVariant(Locale inLocale)

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.

getDisplayName

public final String getDisplayName()

Returns a name for the locale that is appropriate for display to the user. This will be the values returned by getDisplayLanguage(), getDisplayCountry(), and getDisplayVariant() assembled into a single string. The display name will have one of the following forms:

language (country, variant)

language (country)

language (variant)

country (variant)

language

country

variant

depending on which fields are specified in the locale. If the language, country, and variant fields are all empty, this function returns the empty string.

getDisplayName

public String getDisplayName(Locale inLocale)

Returns a name for the locale that is appropriate for display to the user. This will be the values returned by getDisplayLanguage(), getDisplayCountry(), and getDisplayVariant() assembled into a single string. The display name will have one of the following forms:

language (country, variant)

language (country)

language (variant)

country (variant)

language

country

variant

depending on which fields are specified in the locale. If the language, country, and variant fields are all empty, this function returns the empty string.

clone

public Object clone()

Overrides Cloneable

Overrides:

clone in class Object

hashCode

public int hashCode()

Override hashCode. Since Locales are often used in hashtables, caches the value for speed.

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Returns true if this Locale is equal to another object. A Locale is deemed equal to another Locale with identical language, country, and variant, and unequal to all other objects.

Returns:

true if this Locale is equal to the specified object.

Overrides:

equals in class Object