In Unified Modeling Language (UML) sequence diagrams,
you can add synchronous and asynchronous messages to lifelines to
represent the communication between interaction instances. You can
also specify the operations, or methods, of messages.
You must have a sequence diagram with multiple
lifelines open in the diagram editor.
Note: When you
create a synchronous message, a return message is created automatically.
To create a synchronous or asynchronous message:
- In the Palette, click Synchronous
Message or Asynchronous Message.
- In the interaction frame, click a source lifeline and
drag it to a target lifeline.
- Click inside the interaction frame.
- In the Enter Operation Name window,
type a name for the operation and click OK.
Note: If the source lifeline is the same
as the target lifeline, you create a self-directed message.