I have couple of objects:
public class RequestHostel {
private Hostel name;
}
and
public class Hostel {
private String value;
}
and I would like to know if it is possible to group by the value of Hostel, something like
.stream().collect(Collectors.groupingBy(RequestHostel::getName::getValue, counting()))
You cannot chain method reference, but you can use lambda:
.stream().collect(Collectors.groupingBy(rh -> rh.getName().getValue(), counting()))
Or if you're not using these objects, you can simply map them:
.stream().map(RequestHostel::getName).collect(Collectors.groupingBy(Hotel::getValue, counting()))
You cannot chain method references as you did. But yes, you can use lambda for that:
Map<String, Long> countGroupedByValue = requestHostels.stream()
.collect(Collectors.groupingBy(requestHostel -> requestHostel.getName().getValue(),
Collectors.counting()));