Everyone speak about Patterns, Specially Design Patterns.

And I readed a lot about patterns:

• Applying UML & Patterns
• Design Patterns Java Workbook
• Design Patterns
(in fact, I read the french translation of that book, and I can give a tip to our french reader: buy the french edition, it's cheaper than the english one and you will have on the CD the electronical version of the english one. )
• Design Patterns par la pratique
(Yes, I am a french speaking developer. Nobody is perfect ;-) )

But, this month, I discovered what I consider the best book concerning design patterns: Refactoring to Patterns.

And I love it.

The reason is that Joshua explains you how to improve your existing code by refactoring it to a design patterns.

And I really like the fact that when you look at example, you really have impression that you already encountered somewhere in the past. But now, I know how I could enhance it to avoid duplication of code, to facilitate maintenance, ...

The one I prefer is the Replace Implicit Language with Interpreter

In that page, you can only see the source and target UML Diagrams. But, in the book, you have 15 pages explaining motivation, mechanics, example, details of each steps to reach the final design.

And after reading that book, you only want to modify your existing code.

A book to have in your library, between Refactoring book and Design Patterns book.