The Elements of UML 2.0 Style
by Scott W. Ambler

ISBN: 0521616786
Publisher: Cambridge University Press
Pages: 188

This book, like its predecessor covering UML 1.X, presents guidelines for developing effective UML models with good communication value.

The UML has grown significantly with its 2.0 version, and so has this book. Scott Ambler has updated it to include the new diagrams. The book is still physically small enough to be carried around easily, yet its content and applicability are huge.

The included guidelines are written in a way to help teams ensure that they invest their efforts in the right area, focusing on developing software instead of arguing about when to use extend versus include on a use-case diagram (covered by rules 71 and 72 in the book).

Each guideline is followed by a justification and, in some cases, short notes about possible alternatives. These guidelines are very pragmatic and easy to follow, even if experienced modelers are likely to disagree with a few of them.

As Scott Ambler is the founder of Agile Modeling, it shall come as no surprise that the new edition includes diagrams in a hand-written style. Ambler’s intention is to draw focus to the fact that many UML diagrams are drawn on a whiteboard. I believe that the message is of importance (you do not need a heavyweight, expensive CASE tool to benefit from UML), but I question the value of incorporating this diagram style in a book; in my opinion, the diagrams just get harder to read and the point they try to illustrate gets hidden. After all, a hand-drawn diagram that works well on a large whiteboard is less likely to be as clear when presented in a paperback.

Another small disappointment was the treatment of the diagram types new to UML 2.0. For example, the book just adds two guidelines for Interaction Overview Diagrams. My initial feeling is that something is lacking. However, it may be that more guidelines crystallize as the usage of the new diagrams becomes more widespread.

To summarize, despite the minor criticism given above this is a great resource. I would recommend the book to everyone using UML as a valuable reference and style guide.

Reviewed June 2005