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1. Re: Exception Handler support in jBPM 4.4
mwohlf Nov 5, 2010 2:04 PM (in response to bindacandoop)exception handling for jBPM4 comes up every other month it seems, please check out this thread:
http://community.jboss.org/thread/146114
The legendary Ronald van Kuijk pointed out that "handling low level exceptions like java exceptions should normally not 'bubble up' to the processlevel"
and I agree with that.
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2. Re: Exception Handler support in jBPM 4.4
valgoerad Nov 5, 2010 5:41 PM (in response to mwohlf)So, basically, are you saying Process Engine shouldn't help you with "no managed connections" or deadlock transaction kills in any way? That's one of the major reasons I would use a BPM engine for. I mean to be able to configure a "retry" behavior at the process global level instead of doing it in every atomic node that touches the database.
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3. Re: Exception Handler support in jBPM 4.4
mwohlf Nov 5, 2010 6:09 PM (in response to valgoerad)Hi Michal,
There is a retry interceptor in jBPM4 that might do what you are looking for,
did you check out this thread: http://community.jboss.org/thread/154856
I am not sure what you mean by "no managed connections", running out of connections in your pool?
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4. Re: Exception Handler support in jBPM 4.4
dill_2004 Nov 8, 2010 5:06 AM (in response to mwohlf)It seems to me that Michal had in mind discussed problem in http://community.jboss.org/thread/146114,
I' m new in jbpm and I was expecting something to handle errors, something automatic and intelligent, something out of the box,which repeat operations.
Now in ths level of my knowledge, Now I don't see hint given by Ronald
"What I do not get is why you would not want to wrap them in another java class but do want to handle the exeption in a certain node where you most likely need to create custom java classes per class you have.
How many classes are we talking about? 4? 6? 100?
If there are many, you can always look at the implementation of JavaActivity and JavaBehaviour and create ONE custom node that does waht you want AND can direct/steer the process.... So... be creative, be patient, be polite...."I feel in here a lot of repeated xml elements in every jpdl, and maybe repeated code(smells bad practices),
I mean a lot of processes with a lot of activites, component nodes, custom nodes, java nodes in
enterprise,heterogenous environment where is communication beetween different EIS
it was nice to no attention about Connection refused, marshalexception, or any remote exception,or any technical error ...knowing that is mechanism to repeat operation...
It is something pattern in jpdl+java to create handler error which can use transparently and
resolve above problems ?
Best regardsArtur
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5. Re: Exception Handler support in jBPM 4.4
mwohlf Nov 8, 2010 12:44 PM (in response to dill_2004)What I had in mind was something like a NPE because one of your process variables is not initialized, for example a programming error in your form validation.
I don't think low level exceptions like this should be handled in a higher level context like the Process Engine, you could probably initialize a transition into an "error" state but this would violate the "Crash, Don't Trash" principle.
Having said that, I also think it makes sense in some cases to have an exception handling in your process definition. As far as I know this is implemented in jBPM3, see: http://docs.jboss.org/jbpm/v3/userguide/jpdl.html#exceptionhandler.element, unfortunately jBoss stopped development on jBPM4 before this was implemented in jBPM4.
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6. Re: Exception Handler support in jBPM 4.4
valgoerad Nov 9, 2010 3:10 AM (in response to mwohlf)So, the bottom line is, there is no way to do this in jBPM4 for now.
I don't exactly know who's making all the design decisions here so I'll just ask.
Are you planning to implement something like this in the future? I'm asking b/c in all the threads concerning exception handling I see lots of deflecting answers and lots of explanations of why there shouldn't be one in jBPM4.
If you are going to implement it in the end, are you guys willing to accept any patches with possible solutions?
Kind regards,
Michał