From: Bernardi Simona (firstname.lastname@example.org)
Date: Wed 04 Sep 2002 - 14:56:30 BST
Hello, can anybody tell me what is the meaning of "activator" association in the context of sequence diagrams (if there is one) ? The information given in the UML manual (version 1.4) seem to me contradictory, in particular the following statements: 1- each message belonging to an interaction has got an activator message, except for the initial messages (page 2-134) 2- the well-formed rule for Message class: "predecessors must have the same activator as the message" self.allPredecessors->forAll (p|p.activator = self.activator) where self.allPredecessors is the set of all Messages that precede the current one (i.e., self). Since an initial message belongs to (at least) a set of type "m.allPredecessors" where m is a not-initial message belonging to the same interaction, the well-formed rule says that the initial message has an activator. Thanks, Simona.