Browse Books

Reviewer: Edward Miller

Buhr and Casselman attempt to semiformalize (with no inconvenient mathematics to get in the way) a tool that tries to capture how “excellent software engineers have been working for years.” Coming as it does in the midst of the object-oriented revolution, the book is probably best viewed as a kind of realization of the basic notions of object orientation, though this may be a stretch. The main body of the book is a wordy, nonmathematical, conceptual, warm-fuzzy-feeling exposition of the theory and practice of “use case maps,” defined as “structured prose descriptions of interaction scenarios between a system to be designed and the users of the system.” Use case maps have their own graphical notations for concepts; suggestions for symbology; ways of arguing from the notation (in graduate school we were taught never to argue from the notation, because the arguments lead to false results); extrapolating and inferring from the specific to the general; and deducing from the general things (they are not exactly theories) that ought to be true, so are assumed to be. There are worked examples (yielding real C++ code, see below), and informal discussions of hundreds of information theory ideas, management ideas, and just about everything in between. They probably touch every base, but I was too numbed by page 25 to know for certain. Finally, the key to all of this exposition is in Appendix A, with graphical symbols defined for all of the following classes (of objects and subobjects): basic paths (AND fork, AND fork-join, and failure points); structural dynamics (move, move-stay, create, destroy, and copy); coupled paths (asynchronous and synchronous coupling, abort, and “coupling through responsibilities”), and map manipulations (OR join, OR fork, superimposing, factoring, composing, and layering (visible, invisible, layer fold, and layer boundary)). This should give you an idea of the context. Reality arrives after a dozen chapters, in the form of a second a ppendix on C++ that actually includes some C++ code. There are 34 references and a 7-page index to the approximately 300 pages of text.