code: public final ReadOnlyObjectProperty<LocalDate> endDateProperty() {
          if (endDate == null) {
              endDate = new ReadOnlyObjectWrapper<>(this, "endDate", getInterval().getEndDate()); //$NON-NLS-1$
          }
  
          return endDate.getReadOnlyProperty();
      }
docs: A read-only property used for retrieving the end date of the entry. The
  property gets updated whenever the end date inside the entry interval
  changes (see {@link #intervalProperty()}).
  
  @return the end date of the entry