code: public static String formatCurrency(final Number target, final Locale locale) {
  
          Validate.notNull(locale, "Locale cannot be null");
  
          if (target == null) {
              return null;
          }
  
          NumberFormat format = NumberFormat.getCurrencyInstance(locale);
  
          return format.format(target);
      }
docs: Formats a number as a currency value according to the specified locale.
  
  @param target The number to format.
  @param locale Locale to use for formatting.
  @return The number formatted as a currency, or {@code null} if the number
  given is {@code null}.