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UML 2 Activity and Action Models, Part 3: Control Nodes



Conrad E. Bock


This is the third in a series introducing the activity model in the Unified Modeling Language, version 2 (UML 2), and how it integrates with the action model. The previous article addressed the execution characteristics of actions in general, and additional functionality of actions that invoke behaviors. The first article gave an overview of activities and actions that is assumed here. The remainder of the series elaborates other specific elements. This article covers control nodes, which route control and data through the flow model. It also points out the differences in concurrency support between UML 2 and UML 1.x activities.
Journal of Object Technology


action models, control nodes, UML 2, Unified Modeling Language


Bock, C. (2004), UML 2 Activity and Action Models, Part 3: Control Nodes, Journal of Object Technology, [online], (Accessed May 20, 2024)


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Created January 1, 2004, Updated November 10, 2018