Pattern Hatching: Design Patterns Applied [Paperback]

Don't buy this one alone. This is meant to be a supplement to 'Design Patterns'.

The first half of this book is like sitting behind Vlissides while he works at the keyboard, and listening to him talk to himself. It's very informal and conversational. I don't know how well it generalizes to other patterns in other contexts. For some people, though, a concrete example like this seems very helpful.

The second half of the book didn't give me much useful information. It continues the informal, conversational style. This part, however, involves several developers in the process of identifying, characterizing, and sometimes disqualifying candidates for design-pattern-hood. As much as I respect the people in the conversation, that section has a Disney-like fictional quality that I don't like. The old conversations have been reconstructed and morphed into some cleaned-up and picked-over form that reads well. Mostly, they just don't say anything that I can really use.

Seeing an example worked may help some people. On the whole, though, this book has less information per inch of shelf space than many others. Populate your bookshelf accordingly.

It starts analysing the Top Ten Patterns Missconceptions, giving a great view and light on this issue. He groups the misconceptions in 3 groups, being What patterns are, what patterns do and facts about the characteristics of pattern community.

The second chapter gets even better: he copes the design of a Unix like File System design with Design Patterns, using Composite for the Files and Folders, Proxy for the Links, Singleton for users, Visitor for file system commands (he uses Unix cat command as an example), Template Method for single user protection and Mediator for multiuser protection.

Chapter 3 is maybe the best: it goes into some patterns and analyzes where it falls short. He goes into how to kill a singleton, Observer's class and relationship explosion problem (using of course an example!) and how to solution this with an alternative approach with a Visitor. Following, he presents the Generation Gap pattern (which didn't made it to the GoF book) and goes through some other stuff related.

Chapter 4 shows the pattern creation process of the GoF. It is awesome! he tryes to demistify themselves, showing the discussions regarding the Multicast pattern (which didn't made it to the GoF book). He reproduces all the email conversations between the GoF members, showing their pattern creation process filled with great insights.

Finally, chapter 5 offers 7 habits of effective pattern writting.

I've found this book very inspiring. I enjoyed a lot reading it and it gave me the opportunity to see how does the GoF work.

If you enjoyed the GoF book, this is one is for you!!!