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From Gregg Wonderly <ge...@cox.net>
Subject Re: JavaSpace.notify() "not reliable"
Date Fri, 18 May 2007 13:01:27 GMT
Mark Brouwer wrote:
> I think there is one overarching use case and that is that you can't
> draw any conclusions from not receiving any event. A constraint to
> specify you want an immediate first event and at least one event for a
> given time interval provides you the ability to start finding out about
> the cause of not receiving any event after a defined elapsed time.

In the data gathering systems associated with my customers, we call these 
"health check" events.  The devices send their current status at regular 
intervals based on the importance of the device.  They also provide "change 
notices" or perform "report by exception" (RBE) event transmissions so that we 
get timely notification when possible.

This is the kind of thing that I think is important in any type of 
connectionless messaging.  The RMI endpoint model provides connectionless 
messaging, so you need another layer above the connection to establish liveness.

Gregg Wonderly

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