[OO Design Foundation] Steps to Creating Well Designed Software - 6. Activity Diagram

• Is used to describe workflows or business process

Action and Flows

• Activity diagram is started with an intial node drawn as a small filled circle (called initial node)
• Flow is represented by an arrow with an open arrowhead

Decision Node

• Activity diagram can also express conditional logic 
• It is represented by a diamond '♢'
  • It has a single incoming flow and two or more outbound flows
  • Each outbound flow has a guard placed inside square brackets
    • The guard need to be mutually exclusive
    
  • After a decision, the flows can be merged using a merge activity

Concurrent Flow

• Activity diagrams support parallel behavior.
• To express concurrent flows, a fork drawn as a thick horizontal line is used:

Ending the Workflow

• Final node is used to indicate the end of workflow
• Final node is represented as a filled circle placed inside a hollow circle

 

Example

References

• UML and Object-Oriented Design Foundations - https://www.udemy.com/course/uml-and-object-oriented-design-foundations/