Ivar Jacobson

“The key books about object-oriented graphical modeling languages appeared between 1988 and 1992. Leading figures included Grady Booch [Booch,OOAD]; Peter Coad [Coad, OOA], [Coad, OOD]; Ivar Jacobson (Objectory) [Jacobson, OOSE]; Jim Odell [Odell]; Jim Rumbaugh (OMT) [Rumbaugh, insights], [Rumbaugh, OMT]; Sally Shlaer and Steve Mellor [Shlaer and Mellor, data], [Shlaer and Mellor, states] ; and Rebecca Wirfs-Brock (Responsibility Driven Design) [Wirfs-Brock].”

“The analysis model will not be a reflection of what the problem domain looks like... The reason is simply to get a more maintainable structure where changes will be local and thus manageable. We thus do not model reality as it is, as object orientation is often said to do, but we model the reality as we want to see it and to highlight what is important in our application.”

“A {{w|use case}} is a complete course of events in the system, seen from a user’s perspective.”

“The control objects model functionality that is not naturally tied to any other object... We do not believe that the best (most stable) systems are built by only using objects that correspond to real-life entities, something that many other object-oriented analysis and design techniques claim... Behavior that we place in control objects will, in other methods, be distributed over several other objects, making it hard to change this behavior.”

“When a user uses the system, she or he will perform a behaviorally related sequence of transactions in a dialogue with the system. We call such a special sequence a use case.”

“People regard their environment in terms of objects. Therefore it is simple to think in the same way when it comes to designing a model.”