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  1. OMG Issue

UMLR — Conflicting constraints

  • Key: UMLR-711
  • Status: open   Implementation work Blocked
  • Source: Flanders Make ( Klaas Gadeyne)
  • Summary:

    One of the constraints on objectFlows in is

    ObjectNodes connected by an ObjectFlow, with optionally intervening ControlNodes, must have compatible types. In particular, the downstream ObjectNode type must be the same or a supertype of the upstream ObjectNode type.

    It is unclear how this has to be interpreted in the case of two objectNodes with a decisionNode in between. More specifically,

    Imagine a decisionNode with 2 incoming objectFlows:

    • 1 objectFlow, whose target is the decisionNode and whose source is an outputPin of type A
    • 1 objectFlow, whose target is the decisionNode, and whose source is an outputPin of type Boolean. This objectFlow is tagged as the decisionInputFlow of the decisionNode

    The decisionNode also has 2 outgoing objectFlows, guarded by [verdict] and [!verdict] and targeting to (two) inputPins of type A

    Whereas the latter model snippet seems to be a valid model according to the documentation on DecisionNode, the 'compatible_types' constraint does not hold for the connection between the outputpin of type Boolean and any inputPin of type A, since A is not a supertype of boolean.

  • Reported: UML 2.5 — Fri, 14 Oct 2016 10:06 GMT
  • Updated: Wed, 28 Jun 2017 16:24 GMT