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11.3.31 ReadExtentAction




    Action (from BasicActions ) on page 247


   ReadExtentAction is an action that retrieves the current instances of a classifier.


   No additional attributes


   • classifier : Classifier [1..1] The classifier whose instances are to be retrieved.

Issue 8176 -add subsets constraint

   • result : OutputPin [1..1] The runtime instances of the classifier. {Subsets Action::input}


   [1] The type of the result output pin is the classifier.

   [2] The multiplicity of the result output pin is 0..*.,#null)


   The extent of a classifier is the set of all instances of a classifier that exist at any one time.

*Semantic Variation Points

   It is not generally practical to require that reading the extent produce all the instances of the classifier that exist in the entire universe. Rather, an execution engine typically manages only a limited subset of the total set of instances of any classifier and may manage multiple distributed extents for any one classifier. It is not formally specified which managed extent is actually read by a ReadExtentAction .


   No specific notation

   ReadExtentAction is introduced to provide access to the runtime instances of a classifier.

*Changes from previous UML

   ReadExtentAction is unchanged from UML 1.5.