assertArgumentNotNull("locale", locale);

        if (s == null) {
            return null;
        }
        final DecimalFormatSymbols symbols = DecimalFormatSymbolsUtil.getDecimalFormatSymbols(locale);
        final char decimalSep = symbols.getDecimalSeparator();
        final char groupingSep = symbols.getGroupingSeparator();
        final StringBuilder buf = new StringBuilder(20);