Java 8 stream - cast list items to typ of subclass -

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• java 8 stream - check if instanceof 3 answers

i have list of schedulecontainer types , ins stream each element should casted type scheduleintervalcontainer. there way of doing this?

final list<schedulecontainer> scheduleintervalcontainersreducedofsametimes   final list<list<schedulecontainer>> scheduleintervalcontainerofcurrentday = new arraylist<>(         scheduleintervalcontainersreducedofsametimes.stream()             .sorted(comparator.comparing(scheduleintervalcontainer::getstartdate).reversed())             .filter(s -> s.getstartdate().withtimeatstartofday().isequal(today.withtimeatstartofday())).collect(collectors                 .groupingby(scheduleintervalcontainer::getstartdate, linkedhashmap::new, collectors.<schedulecontainer> tolist()))             .values()); 

it's possible, should first consider if need casting @ or function should operate on subclass type beginning.

downcasting requires special care , should first check if given object can casted down by:

object instanceof scheduleintervalcontainer 

then can cast nicely by:

(scheduleintervalcontainer) object 

so, whole flow should like:

collection.stream()     .filter(obj -> obj instanceof scheduleintervalcontainer)     .map(obj -> (scheduleintervalcontainer) obj)     // other operations