Sequence Diagram


is it possible to combine classes and whole systems in a sequence diagram.

For example: There is the class “AuthenticationService” which makes calls to a whole system “Accounting” that is represented as a jar or a remote system ? Or there is the class FileDownloader which makes calls to a FileServer ? Can both be modeled via the LifeLine ?

Is something allowed in the uml standard ?


best regards

I assume you’re asking whether a collection of classes or systems can be represented in a single lifeline.

Yes, lifelines are not restricted to classes or systems. They can be as abstract as you need them to be to represent the sequence you’re trying to capture.