code: static public boolean isDateVetoed(DateVetoPolicy policy, LocalDate date) {
          if (policy == null || date == null) {
              return false;
          }
          return (!policy.isDateAllowed(date));
      }
docs: isDateVetoed, This is a convenience function for checking whether or not a particular date is
  vetoed. Note that veto policies do not have any say about null dates, so this function always
  returns false for null dates.