Object-Oriented Software Development with UML - UNU-IIST ...

Use Cases: Describing Processes 43Concrete descriptions significantly aid comprehension.¢Clients demand specifying their processes in this fashion.¢For prototype purpose.¢7. You may like to rank the use cases to plan which should be taken into the design and implementationphases first.4.2.7 Actors and use cases of the POST systemUsing the techniques of this section, a sample list (not an exhaustive) of relevant actors and use cases theyinitiate include:ActorCashierCustomerManagerSystemAdministratorUse CaseLog InLog OutBuy ItemsRefund ItemsStart UpShut DownAdd New UsersWe leave the construction of the use cases as exercises.4.2.8 Summing upUse case definitionA use case specifies a sequence of actions that the system can perform and that yields an observable resultof value to a particular actor. A use case is full end-to-end story about the use of the system to carry out atask, not an arbitary combination of a number of steps of computation. For example, we should not combinetwo tasks into a use case, such a Borrow a Book and Return a Book, if it is not alway the case that one mustbe carried out after the other.Why use cases?The reasons why use cases are good for requirement capture includeReport No. 259, July 2002UNU/IIST, P.O. Box 3058, Macau