Sequence diagrams
Used to model interactions between entities in a system in a specific scenario
Method calls, and method returns
Arrows representing method calls should be solid arrows. Arrows representing method returns should be dashed arrows.
Type of method calls
Synchronous method calls should have filled arrowheads Asynchronous method calls should have lined arrowheads. (out of scope for 2103T)
Notation specifications for activation bar
Activation bar should start at the arrow pointing to it, and end at the line pointing away from it. An activation bar should also be unbroken until method returns.
Object creation
Object creation
Object deletion
For Java, it can be used to indicate when the point ceases to be referenced (garbage-collected).
Self-invocation (of methods)
Alternative paths
Optional paths
Calls to static methods
Parallel paths
Reference frames
Allows a segment of the interaction to be omitted and shown as a separate sequence diagram
Example
