Initialization Source - modelint/shlaer-mellor-metamodel GitHub Wiki

There may be any number of Data Flows in the Activity housing the Initial Signal Action that contain values necessary to initialize the attribute values of the newly created instance. We need a way to make these values available to the Delegated Creation Activity which creates the instance and sets those values.

An initialization source is exactly that: a Data Flow in the Activity where the initial signal is emitted (the source Activity) holding a value required by the Delegated Creation Activity (the target Activity).

images/activity-subsystem/initialization_source_10.png

In the example above, the Initial Signal Action (ACTN3) triggers the Execute event in the destination Transfer class. The data flow diagram snippet is in the Activity of some Real State. Here we see that Data Flows F2 and F3 carry single instances necessary to determine Attribute Reference initialization on Association R53. Data Flow F4 provides a scalar Tint enum value necessary to initialize a non-referential attribute in the instance to be created. (The Elevator Case Study doesn't actually have a Tint Attribute. It's just there temporarily to test non-referential attribute initialization).

Data Flows F2, F3, and F4, then, constitute Initialization Sources necessary create the new instance.

See R844 to see how these Data Flows are bound to corresponding Data Flows in the target Delegated Creation Activity.

Identifiers

1. Signal action + Signal activity + Domain + Creation activity + Source flow

Attributes

No non-referential attributes.