code: public CurrencyDateCalculatorBuilder<E> ccy1Calendar(final HolidayCalendar<E> ccy1Calendar) {
          if (ccy1Calendar != null) {
              this.ccy1Calendar = ccy1Calendar;
          }
          return this;
      }
docs: The holiday calendar for ccy1, if null or not set, then a default calendar will be used with NO holidays.
  @param ccy1Calendar the Calendar for ccy1
  @return the builder