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Map one object into two models [message #1699554]

Thu, 25 June 2015 06:14

Denis Nikiforov

Messages: 343
Registered: August 2013

Senior Member

Hi

For example I have ModelA, which contains ObjectA.
I need to map ObjectA into ObjectB. But the ObjectB must be contained in two output models ModelB1 and ModelB2.

For example the input model is UML class diagram. And the output models are several XML Schemas generated from one UML model.

The problem is that actually ObjectB is contained only in ModelB1, and the object is missing in ModelB2. I understand the cause of this behavior.
My mapping is executed only once for ModelB1:

mapping ObjectA::map() : ObjectB { }

And the copy ObjectB isn't created for ModelB2. Instead, the transformation gets the same ObjectB from the cache.

But I don't understand how to fix it. Could you guide me?

Thanks!

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Re: Map one object into two models [message #1699555 is a reply to message #1699554]

Thu, 25 June 2015 06:19

Denis Nikiforov

Messages: 343
Registered: August 2013

Senior Member

One solution is to replace all mappings by queries. But it seems too ugly.

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Re: Map one object into two models [message #1699562 is a reply to message #1699555]

Thu, 25 June 2015 07:05

Denis Nikiforov

Messages: 343
Registered: August 2013

Senior Member

The second solution is to execute transformation once for each output model. I think this is a preferred one...

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Re: Map one object into two models [message #1699564 is a reply to message #1699562]

Thu, 25 June 2015 07:29

Rolf Theunissen

Messages: 260
Registered: April 2012

Senior Member

Indeed, running the transformation multiple times is a solution.

Instead of using queries, I think constructors would be the better solution. Constructors are there to construct unique objects.

Another option would be to add a dummy variable to the mapping, to make each call to the mapping unique.

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Re: Map one object into two models [message #1699567 is a reply to message #1699554]

Thu, 25 June 2015 07:46

Ed Willink

Messages: 7655
Registered: July 2009

Senior Member

HI

Each output object must have a distinct identify where the identity is a
tuple of {Mapping, Input1, Input2, ...} so if you want multiple objects
you must ensure multiple identities, possibly just by adding a counter
as an input. I sometimes just add an additional 'disambiguator' object
input to make sure that each call is independent.

Regards

Ed Willink

On 25/06/2015 07:14, Denis Nikiforov wrote:
> Hi
>
> For example I have ModelA, which contains ObjectA.
> I need to map ObjectA into ObjectB. But the ObjectB must be contained
> in two output models ModelB1 and ModelB2.
>
> For example the input model is UML class diagram. And the output
> models are several XML Schemas generated from one UML model.
>
> The problem is that actually ObjectB is contained only in ModelB1, and
> the object is missing in ModelB2. I understand the cause of this
> behavior.
> My mapping is executed only once for ModelB1:
> mapping ObjectA::map() : ObjectB { }
> And the copy ObjectB isn't created for ModelB2. Instead, the
> transformation gets the same ObjectB from the cache.
>
> But I don't understand how to fix it. Could you guide me?
>
> Thanks!

Report message to a moderator