Chapter 5 Building Dynamic Diagrams

Activations

Activations are optional symbols that represent the time required for an action to be performed. They are created on the lifeline of an object. They are purely symbols and do not have property sheets.

An activation can be created in the following diagrams:

Sequence Diagram

In a collaboration diagram, messages that are passed during the period represented by an activation are given sub-numbers. Thus an activation created by message 1, may give rise to messages 1.1 and 1.2.

You can attach or detach a message to an activation. You can also move, resize, and cause the activation to overlap other activations.