I've just posted a reply on exactly the same subject to another user group, so while I've stil got all the arguments in head let me give this one a go.
________________________________________________ Get your own "800" number Voicemail, fax, email, and a lot more http://www.ureach.com/reg/tag ---- On Wed, 21 Nov 2001, Jeremy Ellis ([EMAIL PROTECTED]) wrote: > > Hi all, > > Please be gentle with me, since this is my first post on this forum. > > I realise this is a hotly discussed topic, but I am interested in > feedback > on the issue of using diagrams to capture the processing order within > Use > Cases, particularly Business Use Cases. > > Given that the steps in a Use Cases are often documented using an > Activity > Diagram in Rose, it would be true to say that the sequence of events is > defined in the Activity Diagram, or perhaps a Sequence Diagram or > similar. > <Les>Ok. I like to think of activity diagrams as best describing the internal workings of a use case and sequence diagrams showing how use cases can be sequenced to make up scenarios.</Les> > We are looking at high level Busines Use Cases which effectively would > contain and define the order of other Use Cases, which are thus > "include"d > in the high level one. The question is, since the inclusion of other Use > Cases is specified in the steps of the high level Use Case, would not > the > Activity Diagram representing those steps also contain a reference to > "include" those other Use Cases? > <Les>Ah yes, been here, but I don''t like the term 'high-level use case', because it implies 'mid-level and low-level' use cases, which then gets into decomposition and the next thing you know you're doing structured design with data flow diagrams. I don't believe that use cases that are <<included>> in other use cases should be thought of as at a lower level. The detail in each should be of the same level of abstraction. > I am trying to use the Rational approach, and can find minimal > documentation describing this issue. Any ideas how we might document > such > Use Case sequencing? Is the use of Use Case Realization appropriate here > (by the way, is there any documentation defining the purpose of Use Case > Realizations)? > <Les>Again, I rhink the reason for this is that what you are trying to do is not encouraged by UML. Try to make your use cases sibgle entities that are independent of each other. Only use <<includes>> and <<extends>> to link use cases in order to a) make the diagrams easier to understand, b) make the diagrams easier to maintain, c) to avoid repeating behaviour that occurs in many places.</Les> > Lastly, does anyone have a clear and precise definition of a Business > Use > Case vs a System Use Case? > <Les>I'm purely guessing, that business use cases include behaviour that describes interactions between people (or other actors outside of the scope of the system) whereas system use cases only describe behaviour within the boundary of the system that is being built!</Les> ************************************************************************ * Rose Forum is a public venue for ideas and discussions. * For technical support, visit http://www.rational.com/support * * Admin.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 * *************************************************************************
