class DataFormat {

    @NonNull
    public NumberFormat newNumberFormat() throws IllegalArgumentException {
        NumberFormat result = !numberPattern.isEmpty()
                ? new DecimalFormat(numberPattern, DecimalFormatSymbols.getInstance(getLocaleOrDefault()))
                : NumberFormat.getInstance(getLocaleOrDefault());
        return result;
    }

    private  DataFormat(Locale locale, String datePattern, String numberPattern, Void fake);
    @Deprecated public  DataFormat(@Nullable Locale locale, @Nullable String datePattern);
    @Deprecated public  DataFormat(@Nullable Locale locale, @Nullable String datePattern, @Nullable String numberPattern);

}