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  1. OMG Issue

UMLR — bad example for weight in Figure 15.21

  • Key: UMLR-724
  • Status: open  
  • Source: oose Innovative Informatik eG ( Axel Scheithauer)
  • Summary:

    In the lower diagram on Figure 15.21 an incoming ObjectFlow on a JoinNode has weight=*. As far as I understand this has no effect, since a join node will offer all tokens offered to it to the outgoing ActivityEdge (

    If the joinSpec of a JoinNode evaluates to true, then tokens are offered on the outgoing ActivityEdge of the JoinNode [...]. [Object] Tokens are offered on the outgoing edge in the same order they were offered to the join. [...] The above rules apply to all tokens offered to the JoinNode, including multiple tokens offered from the same incoming edge.

    That means, in the moment, when the joinSpec becomes true, all tokens offered on the incoming Edges, will get offered on the outgoing Edge. The weight doesn't make any difference.

    I'm not sure, whether the same is true for Figure 15.59, where the ObjectFlow out of a DataStore is joined in the same way. Here it would make sense to retrieve the tokens one by one. However I don't see, where the specification would define this. When the DataStore contains 10 tokens, all of them are offered to the outgoing flow, and that means, all of them will be offered to the outgoing flow of a subsequent JoinNode. If we want to retrieve them one by one, the DataStore must offer them to a Pin with Multiplicity 1 directly.
    The examples should get removed, together with the sentence referring to them.

  • Reported: UML 2.5 — Thu, 26 Jan 2017 23:29 GMT
  • Updated: Sat, 28 Jan 2017 15:15 GMT