In Unified Modeling Language (UML) sequence diagrams,
you can move the sending point and the receiving point of an asynchronous
message between lifelines to manipulate the time delay between the
sending event and the receiving event. Multiple messages can occur
between the sending and receiving lifelines.
You must have a sequence diagram that contains
lifelines with asynchronous messages open in the diagram editor.
To delay the receipt of an asynchronous message:
- In the Palette, click Asynchronous
Message.
- Click the source lifeline where you want to start the
message and drag the message first horizontally and then vertically
across existing messages to the target lifeline where you want to
terminate the message.
- Complete one of the following steps:
- If the target lifeline represents an instance of
a structured classifier type, such as a class, name the operation and
click OK.
- If the target lifeline represents an instance of a non-structured
classifier type, such as an actor, rename the selected message and
click OK.
The source lifeline is not blocked and interactions can
occur between the points of the send and receive events.