Check instanceof in stream

Question

I have the following expression:

    scheduleIntervalContainers.stream()
            .filter(sic -> ((ScheduleIntervalContainer) sic).getStartTime() != ((ScheduleIntervalContainer)sic).getEndTime())
            .collect(Collectors.toList());

...where scheduleIntervalContainers has element type ScheduleContainer:

final List<ScheduleContainer> scheduleIntervalContainers

Is it possible to check the type before the filter?

Answer 1

Not exactly a stream, but Guava's FluentIterable does this very cleanly:

FluentIterable.from(scheduleIntervalContainers)
        .filter(ScheduleIntervalContainer.class)
        .filter(sic -> sic.getStartTime() != sic.getEndTime())
        .toList();