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13.3.26 TimeConstraint




    IntervalConstraint (from SimpleTime ) on page 462


   A TimeConstraint defines a Constraint that refers to a TimeInterval .


Issue 8894 - add ‘firstEvent’ entry

   • firstEvent:Boolean [0..1] The value of firstEvent is related to constrainedElement. If firstEvent is true, then the corresponding observation event is the first time instant the execution enters

   constrainedElement. If firstEvent is false, then the corresponding observation event is the last time instant the execution is within constrainedElement.


Issue 8894 -add ‘specification’ entry

   • specification: TimeExpression [1] A time expression used to determine whether the constraint is satisfied. Redefines

   IntervalConstraint ::specification


   No additional constraints


   The semantics of a TimeConstraint is inherited from Constraints. All traces where the constraints are violated are negative traces (i.e., if they occur in practice, the system has failed).


Issue 8349 -replace ‘EventOccurrence’ by ‘OccurrenceSpecification’

   A TimeConstraint is shown as graphical association between a TimeInterval and the construct that it constrains. Typically this graphical association is a small line (e.g., between an OccurrenceSpecification and a TimeInterval ).


   See example in Figure 13.17 where the TimeConstraint is associated with the reception of a Message.

Figure 13.17 - TimeConstraint

   Changes from previous UML

   This metaclass has been added.