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  1. OMG Issue

UMLR — Constraint TemplateSignature::own_elements too constraining

  • Key: UMLR-672
  • Status: open  
  • Source: oose Innovative Informatik eG ( Mr. Axel Scheithauer)
  • Summary:

    The Constraint TemplateSignature::own_elements says:

    Parameters must own the ParameterableElements they parameter or those ParameterableElements must be owned by the TemplateableElement being templated.

    This is not always possible.

    For example in Figure 9.5 a LiteralInteger (sic) is shown as the ParameterableElement. This LiteralInteger is used as the upperValue of the Multiplicity of Property "contents". As such it is owned by the Property and only indirectly by the template "FArray".

    I'm not sure how useful it would be to change the constraint. In Figure 9.5 parameter "k" could also own an InstanceSpecification as ParameterableElement. This would then in turn be used by an InstanceValue as the upperValue of Property "contents". This way it would even be possible to reuse this value in various places across the template (e.g. for other Multiplicities or ValuePins in Activities). I think this would be the preferred way to use Integers as TemplateParameters.

    So unless there are good examples, where the ParameterableElement cannot be owned by the TemplateParameter, the constraint could stay like it is and only the Figures 9.5 and 9.7 must be changed.
    (we could assume that the upperValues are OpaqueExpressions. But if it is not necessary, we should avoid using opaque elements. And even OpaqueExpressions should refer to InstanceSpecifications instead of LiteralIntegers.)

  • Reported: UML 2.5 — Fri, 11 Mar 2016 22:06 GMT
  • Updated: Fri, 11 Mar 2016 22:10 GMT