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  1. OMG Issue

UMLR — Implication of weight of ActivityEdge is unclear

  • Key: UMLR-723
  • Status: open  
  • Source: oose Innovative Informatik eG ( Mr. Axel Scheithauer)
  • Summary:

    The specification says in 15.2.3.3:

    The weight property dictates the minimum number of tokens that must traverse the edge [..]. The minimum number of tokens must then be accepted before any tokens shall traverse the edge.

    The number of tokens accepted by an InputPin is determined by its multiplicity (16.2.3.4):

    InputPins cannot accept more tokens than will be consumed immediately by their Actions during a single execution.

    That means, if the weight is greater than the upper value of the Pin multiplicity tokens can never traverse. The problem is, that the text could be mistaken to mean that the weight overrides the multiplicity. Therefore it should get clarified. With weight=* the problem is even bigger, since the number of tokens that must traverse is not known beforehand, so that the deadlock would depend on the accidental number of tokens waiting.

    Suggestion
    After

    The minimum number of tokens must then be accepted before any tokens shall traverse the edge.

    Add

    Note: If the targeted ObjectNode cannot handle this much tokens this rule leads to no tokens traversing. To avoid this, its upper multiplicity should be at least equal to the weight, even though it is not required by the syntax.

  • Reported: UML 2.5 — Thu, 26 Jan 2017 22:13 GMT
  • Updated: Sat, 28 Jan 2017 15:12 GMT