I guess it would make the api less clean, but I can imagine a sendBatch
method, which returns a single Future that gets triggered only when all
messages in the batch were finished. The callback info could then contain
info about the success/exceptions encountered by each sub-group of
messages. An
Internally it works as you describe, there is only one CountDownLatch per
batch sent, each of the futures is just a wrapper around that.
It is true that if you accumulate thousands of futures in a list that may
be a fair number of objects you are retaining, and there will be some work
involved in
