Part III. The Dynamic Model

In Part II we learned how to define the stable structure or skeleton of the application. But that structure simply exists; it does not actually do anything to solve the customer problem. To actually solve the customer problem a software application must engage in computation.

But that computation must, itself, be done systematically, and it must be complementary to the static model. This part is concerned with developing such a systematic and consistent approach to specifying the dynamic computations needed. That systematic approach has a conceptual framework we call the dynamic model. The cornerstone element of the dynamic model, the object state machine, plays essentially the same role as the object did in the static model.