Use Case Diagram Structure

General Questions/Discussions
1

I am trying to put together a use case diagram. There are a number of functional use cases and one actor. The use cases represent choices for the user but all require that the user first be logged into the system. I have a separate Login use case.

I am wondering how the use case diagram should look. I propose the only two options I can think of below:

  1. Should the user be touching (connected to) the login use case and all other use cases branch from the login use case as dependencies?

OR

  1. Should the user be touching (connected to) all of the activity use cases and the login use case should then be a dependency branching from each activity use case?

This is a bit confusing but I am trying to identify the proper way to represent the login use case which is a dependency for all other use cases. I would like to be consistent with UML standards.

Thanks,
Laura

2

An actor should be connected to all the uses cases where they have a direct interaction with.

So you right, the actor should be connected to the login use case and the other use cases.

If the othr use cases require the actor to be loged in first prior starting the use cases there are two ways of doing this one is messy.

The messy one, each use case can have an <> with the Login use case. But that will make your diagram extreemly messy.

A common misunderstanding is that, use cases are about writting them up they are not really about the pictures. Having said that, you should write in the Pre-Conditions “The “actor” must be succesfully logged in to be able to perform the steps in this use case”

Describing it in the use case either full dress or basic is a “cleaner” way of doing it.

Hope this helps
H.