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13.3.6 CallEvent

Communications


   A CallEvent models the receipt by an object of a message invoking a call of an operation.

*Generalizations

   

    MessageEvent (from Communications ) on page 463

   Description

   A call event represents the reception of a request to invoke a specific operation. A call event is distinct from the call action that caused it. A call event may cause the invocation of a behavior that is the method of the operation referenced by the call request, if that operation is owned or inherited by the classifier that specified the receiver object.

   Attributes

   No additional attributes

   Associations

   • operation: Operation [1] Designates the operation whose invocation raised the call event.

   Constraints

   No additional constraints

   Semantics

   A call event represents the reception of a request to invoke a specific operation on an object. The call event may result in the execution of the behavior that implements the called operation. A call event may, in addition, cause other responses, such as a state machine transition, as specified in the classifier behavior of the classifier that specified the receiver object. In that case, the additional behavior is invoked after the completion of the operation referenced by the call trigger.

   A call event makes available any argument values carried by the received call request to all behaviors caused by this event (such as transition actions or entry actions).

   Notation

   Call events are denoted by a list of names of the triggering operations, followed by an assignment specification:

   <call-event> :: <name> [‘(‘ [<assignment-specification>] ‘)’]<assignment-specification> ::= <attr-name> [‘,’ <attr-name>]*

   where:

   

   <attr-name> is an implicit assignment of the corresponding parameter of the operation to an attribute (with this name) of the context object owning the triggered behavior.

   <assignment-specification> is optional and may be omitted even if the operation has parameters.