Android系統內建了Locale類來定義不同語言，結構很簡單，指定語系、國家程式碼即可初始化一個Locale例項，指定一個語言。

    /**
     * Locale constant for ja_JP.
     */
    public static final Locale JAPAN = new Locale(true, "ja", "JP");

    /**
     * Locale constant for ja.
     */
    public static final Locale JAPANESE = new Locale(true, "ja", "");
 

    public final static Locale Russian = new Locale("ru", "", "");//定義俄文，只指定語系，不指定國家程式碼也可以。
    public final static Locale Arabic = new Locale("ar", "", "");
    public final static Locale Spanish = new Locale("es", "", "");