Locale类：Java本地化

Android提供了丰富的国家化API支持APP的国际化。Java中也有用于转换和划分地区的国际化Locale类位于包java.lang中，国际化在程序中设置语言和时间等时非常有用。

1、Locale类

1.1、构造Locale

①Locale getDefault()：返回当前JVM虚拟机默认的地区语言环境值

②Locale(String language)：构造函数，传入语言码

③Locale(String language, String country)：传入语言和地区码

public Locale(String language, String country) {
        this(language, country, "");
    }

④Locale(String language, String country, String variant)：语言码、国家码及用于指示语言环境变化的任意值。

例：

//默认Locale
    Locale currentLocale = Locale.getDefault();
    
    //指定语言和国家地区
    Locale locale = new Locale("zh", "CN");

1.2、Locale字段

Locale类中提供很多现成的国家Locale实例，可以直接引用使用。

static public final Locale ENGLISH = createConstant("en", "");
    static public final Locale FRENCH = createConstant("fr", "");
    static public final Locale GERMAN = createConstant("de", "");
    static public final Locale ITALIAN = createConstant("it", "");
    static public final Locale JAPANESE = createConstant("ja", "");
    static public final Locale KOREAN = createConstant("ko", "");
    static public final Locale CHINESE = createConstant("zh", "");
    static public final Locale SIMPLIFIED_CHINESE = createConstant("zh", "CN");
    static public final Locale TRADITIONAL_CHINESE = createConstant("zh", "TW");
    static public final Locale FRANCE = createConstant("fr", "FR");
    static public final Locale GERMANY = createConstant("de", "DE");
    static public final Locale ITALY = createConstant("it", "IT");
    static public final Locale JAPAN = createConstant("ja", "JP");
    static public final Locale KOREA = createConstant("ko", "KR");
    static public final Locale CHINA = SIMPLIFIED_CHINESE;
    static public final Locale PRC = SIMPLIFIED_CHINESE;
    static public final Locale TAIWAN = TRADITIONAL_CHINESE;
    static public final Locale UK = createConstant("en", "GB");
    static public final Locale US = createConstant("en", "US");
    static public final Locale CANADA = createConstant("en", "CA");
    static public final Locale CANADA_FRENCH = createConstant("fr", "CA");

例：

Locale china = Locale.CHINA;

2、Locale方法

2.1、getAvailableLocales()

获取Locale支持的全部区域的Locale[]数组，在我电脑上Java 1.8.0_201上运行，支持的Locale共有683之多。

Locale[] locales = Locale.getAvailableLocales();
    for (Locale locale : locales) {
        Log.e("QUIBBLER", locale.getCountry());
    }

(打印Log发现AndroidStudio中如果Log内容为空可能就自动过滤掉)。

2.2、getCountry()

获取Locale对象中的国家地区码

2.3、getLanguage()

返回国家的语言码

2.4、其它方法

Locale类中的其它方法，如下。

Object             clone()
	boolean            equals(Object object)
	static Locale[]    getAvailableLocales()
	static Locale      getDefault()
	String             getDisplayCountry(Locale locale)
	final  String      getDisplayCountry()                 //返回适合向用户显示的国家信息
	final  String      getDisplayLanguage()                //返回适合向用户展示的语言信息
	String             getDisplayLanguage(Locale locale)
	String             getDisplayName(Locale locale)
	final  String      getDisplayName()                    //返回适合向用户展示的语言环境名
	final  String      getDisplayVariant()
	String             getDisplayVariant(Locale locale)
	String             getISO3Country()
	String             getISO3Language()
	static String[]    getISOCountries()
	static String[]    getISOLanguages()
	String             getVariant()
	synchronized int   hashCode()
	final  String      toString()
	synchronized static void   setDefault(Locale locale)