Polymorphic classes in workflow?

Fri Jun 29 05:48:21 EDT 2007

Hi Sergey,

No prob, thanks for your input! I got the binding to work after kicking
myself for missing the obvious.

I would be very interested to know how you handle inheritance of
IF_WORKFLOW. Do you implement IF_WORKFLOW in the subclass or superclass?
My problem is that static components such as FIND_BY_LPOR cannot be
redefined in subclasses, so it needs to go into subclasses. However I am
finding that I actually need to define it at superclass level, and then
end up with a vicious circle where other static components cannot be
redefined in subclasses.

Been messing about with this for several days now... so close yet so far :-)

Cheers,
Mike

On Thu, June 28, 2007 7:50 pm, Breslavets Sergey wrote:
> Hi Mike, Alon: sorry wasn't able to reply earlier.
> Your problem might be in a binding. I use abap classes in my w'flows for
> a while now and polymorphic binding works pretty well for me. I declare
> a superclass in the task container and then can bind any inherited
> subclasses at a runtime. I did that for an HR Master Data maintenance
> where I had a separate subclass to handle each infotype, all inherited
> from a single superclass - the superclass was declared in a task
> container but a particular infotype subclass was used as a runtime. I
> use CL_SWF_EXP_EXPRESSION class to handle the binding to a task object.
>
> Regards,
> Serge
>
> -----Original Message-----
> From: sap-wug-bounces at mit.edu [mailto:sap-wug-bounces at mit.edu] On Behalf
> Of Mike Pokraka
> Sent: Wednesday, June 27, 2007 6:31 AM
> To: SAP Workflow Users' Group
> Subject: RE: Polymorphic classes in workflow?
>
> It would work if it worked.
> I can bind a class *from* a task to an element of type NN, but when I
> try
> to bind it *to* a task's object it simply remains empty. It would be
> sortof polymorphic - in a sense, NN could be considered a
> super-supertype.
> We'd still have to control compatibility, but at least we could use
> interfaces internally in our own developments.
>
> However even if it worked, in effect we'd have to use NNs everywhere and
> I
> don't think complete loss of typing is worth the gain of polymorphic
> behaviour.
>
> Oh and it completely refuses to bind anything to/from sub/supertypes,
> type
> definitions have to match exactly. (Although I'm not too sure that using
> subtypes will simplify matters in my case).
>
> Cheers,
> Mike
>
> On Wed, June 27, 2007 10:54 am, Alon Raskin wrote:
>> Problem with NN (I haven't used it) as I am not sure I can see how it
>> will allow you to leverage polymorphism? You need to be able to
> declare
>> supertypes (or interfaces) to leverage polymorphism. Mike, have you
>> tried declaring a concrete superclass and using that in your binding?
> I
>> wonder if the problem lies in interfaces only?
>>
>> Alon Raskin
>> e: araskin at 3i-consulting.com
>> p: +1 207 523 3489
>> c: +1 207 409 4983
>> f:  +1 806 403-4983
>>
>> -----Original Message-----
>> From: sap-wug-bounces at mit.edu [mailto:sap-wug-bounces at mit.edu] On
> Behalf
>> Of Mike Pokraka
>> Sent: Wednesday, June 27, 2007 4:58 AM
>> To: SAP Workflow Users' Group
>> Subject: RE: Polymorphic classes in workflow?
>>
>> ...doubly frustrating because all the underlying technology allows it.
>> BTW, if you are going to try using NN on a system >620, could you let
> us
>> know if it works? It doesn't on 620 unless I do programmed bindings
>> which
>> kinda defeats the point of simplification.
>>
>> Although... I think it may be possible to develop some kind of generic
>> programmed binding to do the job across various object types. But
> right
>> now time is not a close enough friend to embark on such projects.
>>
>> Cheers,
>> Mike
>>
>> On Tue, June 26, 2007 7:04 pm, Alon Raskin wrote:
>>> Seems like an unnecessary work around (but I will take it). If only
>> SAP
>>> allowed proper polymorphic behaviour....
>>>
>>> ________________________________
>>>
>>> From: sap-wug-bounces at mit.edu on behalf of Mike Pokraka
>>> Sent: Tue 6/26/2007 13:35
>>> To: SAP Workflow Users' Group
>>> Subject: RE: Polymorphic classes in workflow?
>>>
>>>
>>>
>>> There there, actually an answer to your problem may be at hand - you
>> can
>>> enable a type NN (Not Defined) as a container element type as of some
>>> service pack.
>>> This is supposed to work, though I still get no end of
> binding-related
>>> errors. In my case I'm trying to restrict things further than
>> IF_WORKFLOW,
>>> e.g. IF_WF_INVOICE with a number of associated classes for different
>>> purposes.
>>>
>>>
>>> On Tue, June 26, 2007 5:38 pm, Alon Raskin wrote:
>>>> here here.
>>>>
>>>> ________________________________
>>>>
>>>> From: sap-wug-bounces at mit.edu on behalf of Mike Pokraka
>>>> Sent: Tue 6/26/2007 11:21
>>>> To: sap-wug at mit.edu
>>>> Subject: Polymorphic classes in workflow?
>>>>
>>>>
>>>>
>>>> Hi Workflowers,
>>>>
>>>> A very technical question: Has anyone tried to use some sort of
>>>> polymorphism with ABAP classes in workflow?
>>>>
>>>> I am working on 620 at the moment and the trouble is that the WF
>> builder
>>>> doesn't let you specify an interface as a class container element
>> type.
>>>> I
>>>> have even tried to get it to work via inheritance (i.e. binding a
>>>> subtype
>>>> to it's supertype and vice versa) and having spent most of a day on
>> it
>>>> have had no success whatsoever. It seems that the class you define
> is
>>>> the
>>>> class you're stuck with thoughout the WF.
>>>>
>>>> This is rather annoying and negates one of the more useful benefits
>> of
>>>> using classes. Even though I am sitting on a 620 system, I would
> also
>> be
>>>> interested in any experience on NW04/s because it would be handy to
>> know
>>>> how things work and which direction things will go as we also have
>>>> upgrade
>>>> plans around the corner.
>>>>
>>>> Any input appreciated.
>>>> Cheers,
>>>> Mike
>>>>
>>>>
>>>> _______________________________________________
>>>> SAP-WUG mailing list
>>>> SAP-WUG at mit.edu
>>>> http://mailman.mit.edu/mailman/listinfo/sap-wug
>>>>
>>>>
>>>> _______________________________________________
>>>> SAP-WUG mailing list
>>>> SAP-WUG at mit.edu
>>>> http://mailman.mit.edu/mailman/listinfo/sap-wug
>>>>
>>>
>>>
>>> --
>>> Mike Pokraka
>>> Senior Consultant
>>> Workflow Connections
>>> Mobile: +44(0)7786 910855
>>>
>>> _______________________________________________
>>> SAP-WUG mailing list
>>> SAP-WUG at mit.edu
>>> http://mailman.mit.edu/mailman/listinfo/sap-wug
>>>
>>>
>>> _______________________________________________
>>> SAP-WUG mailing list
>>> SAP-WUG at mit.edu
>>> http://mailman.mit.edu/mailman/listinfo/sap-wug
>>>
>>
>>
>> --
>> Mike Pokraka
>> Senior Consultant
>> Workflow Connections
>> Mobile: +44(0)7786 910855
>>
>> _______________________________________________
>> SAP-WUG mailing list
>> SAP-WUG at mit.edu
>> http://mailman.mit.edu/mailman/listinfo/sap-wug
>>
>> _______________________________________________
>> SAP-WUG mailing list
>> SAP-WUG at mit.edu
>> http://mailman.mit.edu/mailman/listinfo/sap-wug
>>
>
>
> --
> Mike Pokraka
> Senior Consultant
> Workflow Connections
> Mobile: +44(0)7786 910855
>
> _______________________________________________
> SAP-WUG mailing list
> SAP-WUG at mit.edu
> http://mailman.mit.edu/mailman/listinfo/sap-wug
>
> _______________________________________________
> SAP-WUG mailing list
> SAP-WUG at mit.edu
> http://mailman.mit.edu/mailman/listinfo/sap-wug
>

-- 
Mike Pokraka
Senior Consultant
Workflow Connections
Mobile: +44(0)7786 910855