An activity diagram is a diagram that shows activities and actions to describe workflows. In the Unified Modeling Language an activity diagram represents the business and operational step-by-step workflows of components in a system. An activity diagram shows the overall flow of control.

Overview

In SysML the activity diagram has been extended to indicate flows among steps that convey physical element (e.g., gasoline) or energy (e.g., torque, pressure). Additional changes allow the diagram to better support continuous behaviors and continuous data flows.

In UML 1.x, an activity diagram is a variation of the UML State diagram in which the "states" represent activities, and the transitions represent the completion of those activities.

Construction

Activity diagrams are typically used for business process modeling. They consist of:

• Initial node.
• Activity final node.
• Activities

The starting point of the diagram is the initial node, and the activity final node is the ending. An activity diagram can have zero or more activity final nodes. In between activities are represented by rounded rectangles.

See also

• Flowchart
• Control flow graph
• Data flow diagram
• Event-driven process chain
• State diagram
• Pseudocode

References

External links

• UML 2.0 Specification Documents
• Introduction to UML 2 Activity Diagrams
• UML 2 Activity Diagram Guidelines
• UML 2 Activity and Action Models