net.jini.io.context.AcknowledgmentSource surprise

While debugging a server context I stumbled into the following server
context element net.jini.io.context.AcknowledgmentSource which was
completely new to me. Looking into the javadoc what its purpose is I
read the following:

   "A server context element for registering interest in receiving an
    acknowledgment that the remote call's result data has been
    delivered to and processed by the client."

To be honest I'm quite pleasantly surprised because I've been coding my
own confirmation logic in the past while it seems it was there all the
time, this is something really useful and also different than what one
can code himself. It might have had a reference in
ServerContext.getServerContext as there is for ClientHost and
ClientSubject because that way I would have certainly discovered it.

Looking further at the method javadoc for the Listener one should
register with an AcknowledgmentSource I read:

   "Handles either receipt of an acknowledgment that the remote call's
    result data has been processed by the client or an indication that no
    acknowledgment will be received.

   If received is true, then a positive acknowledgment has been received
   that the remote call's result data has been processed by the client.
   If received is false, then the implementation of this interface has
   determined that no positive acknowledgment for the associated data
   will be received (perhaps due, for example, to connection failure or
   timeout)."

 From the above it is not clear (to me) whether an invocation made by the
client resulting in e.g. a ServerException as result of (un)marshalling
the result of the invocation results in true or false being passes in
for the notification.

Another point is that there is no mentioning of whether the notification
of the listeners takes place from the same thread as (was) handling the
remote method invocation or that it can be dispatched to a thread pool.
If that is up to the implementation it doesn't harm to make this more
explicit in the spec.
--
Mark

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