public void addCurrency(Currency currency) {
        if (currency.getName().length() == 3 )
        {
            for (Currency curColl : currencyCollections) {
                if (curColl.getName().equals(currency.getName())) {
                    curColl.setValue(currency.getValue());
                    System.out.println(curColl.getName() + "=" + currency.getName() + " обновлена");
                    return;
                }
            }
            currencyCollections.add(currency);
            System.out.println("Добавлена н новая валюта");
        }
        else
            System.out.println("Валюта не три символа");
    }