Activity Diagram - Object Notation

UML Tutorials - Herong's Tutorial Examples

∟Activity Diagram - Object Notation

This section describes the Object Notation used in a UML Activity Diagram. An Object Notation represents an object generated by one action and consumed by the next action.

An Object Notations is a graphical notation used in a UML Activity Diagram to represent an object, which could be an input and/or an output of an action. An object in this case is considered as an instance of a class in a given state.

An Object Notation is drawn as a rectangle with its name placed inside, which can also be qualified by a state written within brackets below the name.

For example, the "Order [Filled]" object generated from the "Fill Order" action will be consumed by the "Ship Order" action. This object can be drawn as an Object Notation in a UML activity diagram as shown below: