UML Communication Diagram

Communication Diagram⌘

• Describes interactions between objects.
• The sequencing of Messages is given through a sequence numbering scheme.
• Communication Diagrams correspond to simple Sequence Diagrams.
• Lifeline represents an individual participant in the interaction.

Message⌘

• A message is shown as a line from the sender to the receiver.
• The send and receive events may both be on the same lifeline.
• The form of the line or arrowhead reflects properties of the message:
  • Synchronous message (send message and suspend execution while waiting for response)
  • Asynchronous message (send message and proceed immediately without waiting)
  • Reply message (reply to synchronous message)

Entity-Control-Boundary Pattern⌘

• Entity: objects representing system data
• Control: objects that manages the flow of interaction of the scenario (the logic of a system)
• Boundary: objects that interface with system actors

Entity-Control-Boundary Links⌘

	Actor	Boundary	Control	Entity
Actor		OK
Boundary	OK		OK
Control		OK	OK	OK
Entity			OK	OK