code: public boolean isTimeAllowed(LocalTime time) {
          if (time == null) {
              return allowEmptyTimes;
          }
          return (!(InternalUtilities.isTimeVetoed(vetoPolicy, time)));
      }
docs: isTimeAllowed, This checks to see if the specified time is allowed by any currently set veto
  policy, and allowed by the current setting of allowEmptyTimes.
  
  If allowEmptyTimes is false, and the specified time is null, then this returns false.
  
  If a veto policy exists, and the specified time is vetoed, then this returns false.
  
  If the time is not vetoed, or if empty times are allowed and the time is null, then this
  returns true.