A Message defines a particular communication between Lifelines of an Interaction, such as raising a Signal, invoking an Operation, or creating or destroying an Instance. Messages specify the kind of communication, the sender, and the receiver.
A Message is represented by arrows between the lifelines. The style of the Message line and arrowhead reflect the types of the Message.
You can see the description of a selected property in the description area of the Specification window. To see descriptions, be sure the Show Description option is selected.
Message sorts
Message Sort
Description
Example
synchCall
The Message was generated by a synchronous call to an Operation. Synchronous Messages can overtake each other. When a Message represents an Operation, the arguments of the Message must correspond to the parameters of the Operation.
asynchCall
Asynchronous means that the caller continues immediately after the call. asynchCall Messages do not have reply Messages.
asynchSignal
The Message was generated by an asynchronous send Action. The argument of the Message must correspond to the attributes of the Signal.
reply
A reply Message to an Operation call.
createMessage
The Message designates the creation of another Lifeline object. No other Messages on a given Lifeline in an Interaction operand may appear above a Lifeline.
deleteMessage
The Message designates the termination of another Lifeline.
Message syntax
The Message name is displayed on the message path on the diagram pane. The syntax of the message name is as follows: