code: public void setInternationalCurrencySymbol(String currencyCode)
      {
          intlCurrencySymbol = currencyCode;
          currency = null;
          if (currencyCode != null) {
              try {
                  currency = Currency.getInstance(currencyCode);
                  currencySymbol = currency.getSymbol(locale);
              } catch (IllegalArgumentException e) {
              }
          }
          //cachedIcuDFS = null;
      }
docs: Sets the ISO 4217 currency code of the currency of these
  DecimalFormatSymbols.
  If the currency code is valid (as defined by
  {@link java.util.Currency#getInstance(java.lang.String) Currency.getInstance}),
  this also sets the currency attribute to the corresponding Currency
  instance and the currency symbol attribute to the currency's symbol
  in the DecimalFormatSymbols' locale. If the currency code is not valid,
  then the currency attribute is set to null and the currency symbol
  attribute is not modified.
  
  @param currencyCode the currency code
  @see #setCurrency
  @see #setCurrencySymbol
  @since 1.2