CLIENT_ACKNOWLEDGE optimization

[ovidiu.feodorov]

Message.acknowledge() individually acknowledges each message accumulated by the session, in case that the acknowledgment mode is CLIENT_ACKNOWLEDGE.

It makes sense to have a special server call, acknowledgeBulk(messageID, destination, receiverID) - unless a better method name comes up- that acknowledges this specific message and ALL messages that have previously been sent to this receiver. It's more efficient, we save unecessary network calls.

[timfox]

Absolutely.

I left this one for now, since I considered it an optimisation not necessary to get us through the basic compliance for the non distributed alpha.

Actually also the DUPS_OK_ACKNOWLEDGE mode is non optimised too - currently it just works as AUTO_ACKNOWLEDGE which I believe is compliant but obviously not optimal.

It's likely both of these could use the same operation to send their batch of messages to the server.

[ovidiu.feodorov]

http://jira.jboss.org/jira/browse/JBMESSAGING-82