An activity in

Unified Modeling Language The Unified Modeling Language (UML) is a general-purpose visual modeling language that is intended to provide a standard way to visualize the design of a system. UML provides a standard notation for many types of diagrams which can be roughly ...

(UML) is a major task that must take place in order to fulfill an operation contract. The ''Student Guide to Object-Oriented Development'' defines an activity as a "sequence of activities that make up a process." Activities can be represented in activity diagrams. The word ''Activity'' is often confused with that of '' Action'', which describes a step within an activity. An activity can represent: * The invocation of an operation. * A step in a

business process A business process, business method, or business function is a collection of related, structured activities or tasks performed by people or equipment in which a specific sequence produces a service or product (that serves a particular business g ...

. * An entire business process. Activities can be decomposed into subactivities, until at the bottom we find atomic actions. The entire activity can be enclosed in a rounded rectangle called an "Activity Frame", with the name of the activity listed in the upper left corner, although it is often omitted. The underlying conception of an activity has changed between UML 1.5 and UML 2.0. In UML 2.0 an activity is no longer based on the state-chart rather it is based on a Petri net like coordination mechanism. There the activity represents user-defined behavior coordinating actions. Actions in turn are pre-defined (UML offers a series of actions for this).

Literature

* Conrad Bock:
UML 2 Activity and Action Models
', in Journal of Object Technology, vol. 2, no. 4, July-August 2003, pp. 43-53 * Conrad Bock:
UML 2 Activity and Action Models Part 2: Actions
', in Journal of Object Technology, vol. 2, no. 5, pp. 41-56 * Conrad Bock:
UML 2 Activity and Action Models Part 3: Control Nodes
', in Journal of Object Technology, vol. 2, no. 6, pp. 7-23 * Conrad Bock:
UML 2 Activity and Action Models Part 4: Object Nodes
', in Journal of Object Technology, vol. 3, no. 1, pp. 27-41

References

{{DEFAULTSORT:Activity (Uml) Unified Modeling Language