Hi Amit,
confirmed, this is currently not supported by the HANA JDBC driver.
I've no idea on whether or not this is on the to-do-list (but would guess so), so for now you can't expect this feature to be present soon.
At the moment I don't see a way to save the two calls and just perform one.
If you don't actually need to know the generated number after you created the record, you could just include the <sequence_name>.nextval call in the INSERT statement.
After the call you can fetch the current value via <sequence_name>.curval - but that would just be another call as well.
- Lars
