1.2.5.1 BpmnMessage
A Message represents the content of a communication between two Participants. In BPMN 2.0, a Message is a graphical object (it was a supporting element in BPMN 1.2). An ItemDefinition is used to specify the Message structure. In a Process that is not used in a Collaboration, the communication is not displayed, but a Message can be defined for Activities that send and receive Messages (such as a Send Task?see Figure 8.33). Note that the display of Messages in a Process, Collaboration, or Choreography is optional. Ownership: A message belongs to a collaboration
BpmnRootElementBpmnMessageBpmnItemDefinition
Association
Description
ItemRef : BpmnItemDefinition [0..1]
Sender : BpmnSendTask [0..*]
A Message for the messageRef attribute MAY be entered. This indicates that the Message will be sent by the Task. The Message in this context is equivalent to an out-only message pattern (Web service). One or more corresponding outgoing Message Flow MAY be shown on the diagram. However, the display of the Message Flow is not required. The Message is applied to all outgoing Message Flow and the Message will be sent down all outgoing Message Flow at the completion of a single instance of the Task.
MessageFlow : BpmnMessageFlow [0..*]
Receiver : BpmnReceiveTask [0..*]
A Message for the messageRef attribute MAY be entered. This indicates that the Message will be received by the Task. The Message in this context is equivalent to an in-only message pattern (Web service). One or more corresponding incoming Message Flow MAY be shown on the diagram. However, the display of the Message Flow is not required. The Message is applied to all incoming Message Flow, but can arrive for only one of the incoming Message Flow for a single instance of the Task.
EventDefinition : BpmnMessageEventDefinition [0..*]
InputMessage : BpmnOperation [0..*]
specifies the input Message of the Operation. An Operation has exactly one input Message.
OutputMessage : BpmnOperation [0..*]
specifies the output Message of the Operation. An Operation has at most one input Message.
1.2.5.1.1 Consistency rules
A message can always belong to a collaboration