> > 2. May I have an actor that does not interact with an UC? For > > example, I have two actors, CIC and PV, these actors have a parent > > actor called “CA”. If the actor “CA” does not interact >with an UC, is > > this a valid actor? And if only the actor “CA” interact with an UC, > > are “CIC” and “PV” valid actors? > > There are few reasons why you might want to do this, but in > general I'd agree with Les and say don't do it. Remember, > the underlying purpose of an Actor in UML is to document the > interaction between the system and a particular class of user > of the system. If there is no interaction, the actor tends to be > superfluous. There are, however, a few cases where showing > such actors can, nevertheless, convey useful information > about the system and its context, so I would say, if adding > these extra actors does indeed convey useful information, > go ahead and add them. > Let me give a brief example of situations where this occurs.
We have a series of actors using the system. I capture these in an actors diagram. Let's call them Manager and Developer. Now the manager insists on having all the capabilities of a developer plus some of their own that the developer doesn't have. When showing a developer interacting with the system, you also have to show the manager having the same capability. Now we can't have two actors initiating the use case (developer and manager). We don't want to duplicate the functionality of a use case. So we create a 'User' actor who takes the role of a developer + manager. Now whenever we want to show a developer initiating a use case we use 'user' instaed, to indicate that the manager may also be the initiator. The developer is never shown on a use case diagram, but many would still feel it important to retain the role of a developer as an actor in the use case model. Les. ________________________________________________ Get your own "800" number Voicemail, fax, email, and a lot more http://www.ureach.com/reg/tag ************************************************************************ * Rose Forum is a public venue for ideas and discussions. * For technical support, visit http://www.rational.com/support * * Post or Reply to: [EMAIL PROTECTED] * Subscription Requests: [EMAIL PROTECTED] * Archive of messages: * http://www.rational.com/support/usergroups/rose/rose_forum.jsp * Other Requests: [EMAIL PROTECTED] * * To unsubscribe from the list, please send email * To: [EMAIL PROTECTED] * Subject: <BLANK> * Body: unsubscribe rose_forum *************************************************************************
