From: SpamSpamSpam <spam@spam.com>
Subject: Re: Extended comm loss and TCP/IP
Date: 1999/04/15
Date: 1999-04-15T00:00:00+00:00 [thread overview]
Message-ID: <3715C3E5.46C5704B@spam.com> (raw)
In-Reply-To: 37142321.E3B0C8BE@pacbell.net
Hi Mark,
Your problem is CORBA specific, though if ORBExpress raised a COMMS_FAILURE
exception within the client this would help! Theres a book "CORBA Design
Patterns" that
you might consider. Its on my list..........
For an Ada view :)...
You could make ALL the calls "oneway" and then enter a guarded "select"
which accepts
a callback with the specified delay period or assumes a comms failure, but
this requires alot
of extra work for an exceptional condition the ORB should detect and report.
It would be better if ORBExpress on the client side "polled" the server
while awaiting responses,
raising the COMMS_FAILURE exception if the ORB server side failed to
respond. After all this
is all meant to be invisible to you (including the TCP/IP networking).
Alternative - Wrap your calls
in tasks, assume comms failure and surprise yourself with a completion
exception !
-------------------------------------------------------------------------------------------
with CorbaCallXWrap ;
procedure Client is
begin
-- blar, blar , blar .....
declare
CorbaCall : CorbaCallXWrap.Object ; -- kick off call
RoughTimeout : constant Duration := 600 ;
begin
Delay ( RoughTimeout ) ;
-- Comms fail code here
-- raise COMMS_FAILURE for example
exception
when CorbaCallXWrap.Finished => null ;
end ;
-- blar, blar , blar
end Client ;
---------------------------------------------------------------------------------
package CorbaCallXWrap is
task type Object ;
Finished : exception ;
end CorbaCallXWrap ;
-----------------------------------------------------------------------------------
package body CorbaCallXWrap is
-- Dummy real would with in
procedure CorbaCall is begin null ; end ;
task body Object is
Finished : exception ;
begin
CorbaCall ;
raise Finished ;
end Object ;
end CorbaCallXWrap ;
Cheers Glen
next prev parent reply other threads:[~1999-04-15 0:00 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-04-13 0:00 Extended comm loss and TCP/IP Mark McKercher
1999-04-15 0:00 ` tim gilbert
1999-04-15 0:00 ` Corey Ashford
1999-04-15 0:00 ` SpamSpamSpam [this message]
1999-04-15 0:00 ` SpamSpamSpam
1999-04-15 0:00 ` SpamSpamSpam
1999-04-15 0:00 ` SpamSpamSpam
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