UML Tutorials - Herong's Tutorial Examples - v1.05, by Herong Yang
What Is an Activity Diagram?
This section describes the UML Activity Diagram, which presents behaviors of a system by showing execution sequences of activities of the system.
What Is an Activity Diagram? An Activity Diagram is a diagram that describes internal behaviors of a single activity by showing execution sequences of actions that are needed to complete the activity.
In the OMG UML 2.4.1 specification, Activity Diagram is referred as: Activity modeling emphasizes the sequence and conditions for coordinating lower-level behaviors, rather than which classifiers own those behaviors. These are commonly called control flow and object flow models. The actions coordinated by activity models can be initiated because other actions finish executing, because objects and data become available, or because events occur external to the flow.
The picture below shows you a good example of an Activity Diagram describing internal behaviors of an activity called Process Order with sequenced actions:
Table of Contents
Introduction of UML (Unified Model Language)
UML Class Diagram and Notations
►UML Activity Diagram and Notations
Activity Diagram - Action Notation
Activity Diagram - Control Flow Notation
Activity Diagram - Start and Final Notations
Activity Diagram - Decision Notation
Activity Diagram - Merge Notation
Activity Diagram - Fork Notation
Activity Diagram - Join Notation
Activity Diagram - Object Notation
Activity Diagram - Send Signal Notation
Activity Diagram - Accept Event Notation
Activity Diagram - Partition (Swimlane) Notation
Activity Diagram - Frame Notation and Parameters
UML Sequence Diagram and Notations
UML State Machine Diagram and Notations
UML Use Case Diagram and Notations