Pattern Hatching

John Vlissides is a member of the research staff at the IBM T. J. Watson Research Center in Hawthorne, New York. He has practiced object-oriented technology for more than a decade as a designer, implementer, researcher, lecturer, and consultant. In addition to co-authoring Design Patterns: Elements of Reusable Object-Oriented Software, he is co-editor of the book Pattern Languages of Program Design 2 (both from Addison-Wesley). He and the other co-authors of Design Patterns are recipients of the 1998 Dr. Dobb's Journal Excellence in Programming Award. 0201432935AB04062001

• Contents....v Foreword....vii Preface....xi CHAPTER 1 Introduction....1 The Top Ten Misconceptions....3 Observations....9 CHAPTER 2 Designing with Patterns....11 Fundamentals....12 Orphans, Adoption, and Surrogates....16 "But Where Do Surrogates Fit into This?"....21 Visiting Rights....26 Visitor Caveats....33 Single-User Protection....34 Multiuser Protection....41 Wrapping Up....52 CHAPTER 3 Themes and Variations....55 To Kill a Singleton....55 The Trouble with Observer....65 Visitor Revisited....71 Generation Gap....77 Type Laundering....92 Thanks for the Memory Leaks....100 Pushme-Pullyu....103 CHAPTER 4 Labor of Love....111 CHAPTER 5 Seven Habits of Effective Pattern Writers....133 Habit 1: Taking Time to Reflect....134 Habit 2: Adhering to a Structure....135 Habit 3: Being Concrete Early and Often....136 Habit 4: Keeping Patterns Distinct and Complementary....136 Habit 5: Presenting Effectively....137 Habit 6: Iterating Tirelessly....138 Habit 7: Collecting and Incorporating Feedback....139 No Silver Bullet....140 Bibliography....141 Index....145