public static final class Locale.Builder extends Object
Builder is used to build instances of Locale
 from values configured by the setters.  Unlike the Locale
 constructors, the Builder checks if a value configured by a
 setter satisfies the syntax requirements defined by the Locale
 class.  A Locale object created by a Builder is
 well-formed and can be transformed to a well-formed IETF BCP 47 language tag
 without losing information.
 Note: The Locale class does not provide any
 syntactic restrictions on variant, while BCP 47 requires each variant
 subtag to be 5 to 8 alphanumerics or a single numeric followed by 3
 alphanumerics.  The method setVariant throws
 IllformedLocaleException for a variant that does not satisfy
 this restriction. If it is necessary to support such a variant, use a
 Locale constructor.  However, keep in mind that a Locale
 object created this way might lose the variant information when
 transformed to a BCP 47 language tag.
 
The following example shows how to create a Locale object
 with the Builder.
 
 
     Locale aLocale = new Builder().setLanguage("sr").setScript("Latn").setRegion("RS").build();
 
 
 Builders can be reused; clear() resets all
 fields to their default values.
Locale.forLanguageTag(java.lang.String)| Constructor and Description | 
|---|
| Builder()Constructs an empty Builder. | 
| Modifier and Type | Method and Description | 
|---|---|
| Locale.Builder | addUnicodeLocaleAttribute(String attribute)Adds a unicode locale attribute, if not already present, otherwise
 has no effect. | 
| Locale | build()Returns an instance of  Localecreated from the fields set
 on this builder. | 
| Locale.Builder | clear()Resets the builder to its initial, empty state. | 
| Locale.Builder | clearExtensions()Resets the extensions to their initial, empty state. | 
| Locale.Builder | removeUnicodeLocaleAttribute(String attribute)Removes a unicode locale attribute, if present, otherwise has no
 effect. | 
| Locale.Builder | setExtension(char key,
            String value)Sets the extension for the given key. | 
| Locale.Builder | setLanguage(String language)Sets the language. | 
| Locale.Builder | setLanguageTag(String languageTag)Resets the Builder to match the provided IETF BCP 47
 language tag. | 
| Locale.Builder | setLocale(Locale locale)Resets the  Builderto match the providedlocale. | 
| Locale.Builder | setRegion(String region)Sets the region. | 
| Locale.Builder | setScript(String script)Sets the script. | 
| Locale.Builder | setUnicodeLocaleKeyword(String key,
                       String type)Sets the Unicode locale keyword type for the given key. | 
| Locale.Builder | setVariant(String variant)Sets the variant. | 
public Builder()
public Locale.Builder setLocale(Locale locale)
Builder to match the provided
 locale.  Existing state is discarded.
 All fields of the locale must be well-formed, see Locale.
 
Locales with any ill-formed fields cause
 IllformedLocaleException to be thrown, except for the
 following three cases which are accepted for compatibility
 reasons:
locale - the localeIllformedLocaleException - if locale has
 any ill-formed fields.NullPointerException - if locale is null.public Locale.Builder setLanguageTag(String languageTag)
clear().  Grandfathered tags (see Locale.forLanguageTag(java.lang.String)) are converted to their canonical
 form before being processed.  Otherwise, the language tag
 must be well-formed (see Locale) or an exception is
 thrown (unlike Locale.forLanguageTag, which
 just discards ill-formed and following portions of the
 tag).languageTag - the language tagIllformedLocaleException - if languageTag is ill-formedLocale.forLanguageTag(String)public Locale.Builder setLanguage(String language)
language is the empty string or
 null, the language in this Builder is removed.  Otherwise,
 the language must be well-formed
 or an exception is thrown.
 The typical language value is a two or three-letter language code as defined in ISO639.
language - the languageIllformedLocaleException - if language is ill-formedpublic Locale.Builder setScript(String script)
script is null or the empty string,
 the script in this Builder is removed.
 Otherwise, the script must be well-formed or an
 exception is thrown.
 The typical script value is a four-letter script code as defined by ISO 15924.
script - the scriptIllformedLocaleException - if script is ill-formedpublic Locale.Builder setRegion(String region)
Builder is removed.  Otherwise,
 the region must be well-formed or an
 exception is thrown.
 The typical region value is a two-letter ISO 3166 code or a three-digit UN M.49 area code.
The country value in the Locale created by the
 Builder is always normalized to upper case.
region - the regionIllformedLocaleException - if region is ill-formedpublic Locale.Builder setVariant(String variant)
Builder is removed.  Otherwise, it
 must consist of one or more well-formed
 subtags, or an exception is thrown.
 Note: This method checks if variant
 satisfies the IETF BCP 47 variant subtag's syntax requirements,
 and normalizes the value to lowercase letters.  However,
 the Locale class does not impose any syntactic
 restriction on variant, and the variant value in
 Locale is case sensitive.  To set such a variant,
 use a Locale constructor.
variant - the variantIllformedLocaleException - if variant is ill-formedpublic Locale.Builder setExtension(char key, String value)
Note: The key UNICODE_LOCALE_EXTENSION ('u') is used for the Unicode locale extension.
 Setting a value for this key replaces any existing Unicode locale key/type
 pairs with those defined in the extension.
 
Note: The key 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.
key - the extension keyvalue - the extension valueIllformedLocaleException - if key is illegal
 or value is ill-formedsetUnicodeLocaleKeyword(String, String)public Locale.Builder setUnicodeLocaleKeyword(String key, String type)
Keys and types are converted to lower case.
Note:Setting the 'u' extension via setExtension(char, java.lang.String)
 replaces all Unicode locale keywords with those defined in the
 extension.
key - the Unicode locale keytype - the Unicode locale typeIllformedLocaleException - if key or type
 is ill-formedNullPointerException - if key is nullsetExtension(char, String)public Locale.Builder addUnicodeLocaleAttribute(String attribute)
attribute - the attributeNullPointerException - if attribute is nullIllformedLocaleException - if attribute is ill-formedsetExtension(char, String)public Locale.Builder removeUnicodeLocaleAttribute(String attribute)
Attribute comparision for removal is case-insensitive.
attribute - the attributeNullPointerException - if attribute is nullIllformedLocaleException - if attribute is ill-formedsetExtension(char, String)public Locale.Builder clear()
public Locale.Builder clearExtensions()
setExtension(char, String)public Locale build()
Locale created from the fields set
 on this builder.
 This applies the conversions listed in Locale.forLanguageTag(java.lang.String)
 when constructing a Locale. (Grandfathered tags are handled in
 setLanguageTag(java.lang.String).)
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