Activity (UML)

An activity in Unified Modeling Language (UML) is a major task that must take place in order to fulfill an operation contract. Activities can be represented in activity diagrams

An activity can represent:

• The invocation of an operation.
• A step in a business process.
• An entire business process.

Activities can be decomposed into subactivities, until at the bottom we find atomic actions.

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).

Unified Modeling Language Actors Organizations Object Management Group UML Partners Persons Grady Booch Ivar Jacobson James Rumbaugh Concepts Object oriented Object-oriented programming Object-oriented analysis and design Object-oriented modeling Structure Actor Attribute Artifact Class Component Interface Object Package Profile diagram Behavior Activity Event Message Method State Use case Relationships Aggregation Association Composition Dependency Generalization (or Inheritance) Extensibility Profile Stereotype Other Multiplicity Diagrams Structure Class Component Composite structure Deployment Object Package Behaviour Activity State Machine Use case Interaction Communications Sequence Interaction overview Timing Derived languages Systems Modeling Language (SysML) UML eXchange Format (UXF) XML Metadata Interchange (XMI) Executable UML (xUML) Other topics Glossary of UML terms Rational Unified Process Comparison of UML tools UML colors