Are tokens ever considered model elements in activity diagrams?

Are tokens ever considered model elements in activity diagrams?

• A. Yes
• B. No
• C. Sometimes
• D. Only in certain diagrams

Answer: (B)

Tokens in activity diagrams are about how the activity runs, not about what is statically defined. In UML, the things you model—the Activity itself, the Actions, the Control Nodes, and the Edges—are model elements. Tokens, such as control tokens and object tokens, are runtime artifacts created by the execution engine to show the flow of control and data as the activity progresses. They exist only during execution and don’t become part of the static model, so they aren’t considered model elements. Some tools may animate tokens to illustrate flow, but that visualization reflects execution behavior, not additional modeling constructs.

Tokens in activity diagrams are about how the activity runs, not about what is statically defined. In UML, the things you model—the Activity itself, the Actions, the Control Nodes, and the Edges—are model elements. Tokens, such as control tokens and object tokens, are runtime artifacts created by the execution engine to show the flow of control and data as the activity progresses. They exist only during execution and don’t become part of the static model, so they aren’t considered model elements. Some tools may animate tokens to illustrate flow, but that visualization reflects execution behavior, not additional modeling constructs.