Preface xiiiChapter 1 Introduction 1
Why Patterns? 1
Why Design Patterns? 2
Why Java? 3
UML 4
Challenges 4
The Organization of This Book 5
Welcome to Oozinoz! 6
Summary 7
Part I Interface Patterns 9Chapter 2 Introducing Interfaces 11
Interfaces and Abstract Classes 11
Interfaces and Obligations 13
Summary 15
Beyond Ordinary Interfaces 16
Chapter 3 Adapter 17
Adapting to an Interface 17
Class and Object Adapters 21
Adapting Data for a JTable 25
Identifying Adapters 30
Summary 31
Chapter 4 Facade 33
Facades, Utilities, and Demos 33
Refactoring to Facade 35
Summary 46
Chapter 5 Composite 47
An Ordinary Composite 47
Recursive Behavior in Composites 48
Composites, Trees, and Cycles 50
Composites with Cycles 56
Consequences of Cycles 60
Summary 60
Chapter 6 Bridge 63
An Ordinary Abstraction: On the Way to Bridge 63
From Abstraction to Bridge 66
Drivers as Bridges 68
Database Drivers 69
Summary 71
Part II Responsibility Patterns 73Chapter 7 Introducing Responsibility 75
Ordinary Responsibility 75
Controlling Responsibility with Visibility 77
Summary 79
Beyond Ordinary Responsibility 79
Chapter 8 Singleton 81
Singleton Mechanics 81
Singletons and Thread 83
Recognizing Singleton 84
Summary 86
Chapter 9 Observer 87
A Classic Example: Observer in GUIs 87
Model/View/Controller 92
Maintaining an Observable Object 99
Summary 101
Chapter 10 Mediator 103
A Classic Example: GUI Mediators 103
Mediators of Relational Integrity 108
Summary 116
Chapter 11 Proxy 117
A Classic Example: Image Proxies 117
Image Proxies Reconsidered 122
Remote Proxies 125
Dynamic Proxies 131
Summary 136
Chapter 12 Chain of Responsibility 137
An Ordinary Chain of Responsibility 137
Refactoring to Chain of Responsibility 139
Anchoring a Chain 142
Chain of Responsibility without Composite 144
Summary 144
Chapter 13 Flyweight 145
Immutability 145
Extracting the Immutable Part of a Flyweight 146
Sharing Flyweights 148
Summary 152
Part III Construction Patterns 153Chapter 14 Introducing Construction 155
A Few Construction Challenges 155
Summary 157
Beyond Ordinary Construction 157
Chapter 15 Builder 159
An Ordinary Builder 159
Building under Constraints 162
A Forgiving Builder 164
Summary 165
Chapter 16 Factory Method 167
A Classic Example: Iterators 167
Recognizing Factory Method 168
Taking Control of Which Class to Instantiate 169
Factory Method in Parallel Hierarchies 171
Summary 173
Chapter 17 Abstract Factory 175
A Classic Example: GUI Kits 175
Abstract Factories and Factory Method 180
Packages and Abstract Factories 184
Summary 185
Chapter 18 Prototype 187
Prototypes as Factories 187
Prototyping with Clones 189
Summary 192
Chapter 19 Memento 193
A Classic Example: Using Memento for Undo 193
Memento Durability 201
Persisting Mementos Across Sessions 201
Summary 205
Part IV Operation Patterns 207Chapter 20 Introducing Operations 209
Operations and Methods 209
Signatures 211
Exceptions 212
Algorithms and Polymorphism 213
Summary 214
Beyond Ordinary Operations 215
Chapter 21 Template Method 217
A Classic Example: Sorting 217
Completing an Algorithm 221
Template Method Hooks 224
Refactoring to Template Method 225
Summary 228
Chapter 22 State 229
Modeling States 229
Refactoring to State 233
Making States Constant 238
Summary 240
Chapter 23 Strategy 241
Modeling Strategies 241
Refactoring to Strategy 244
Comparing Strategy and State 248
Comparing Strategy and Template Method 249
Summary 250
Chapter 24 Command 251
A Classic Example: Menu Commands 251
Using Command to Supply a Service 254
Command Hooks 255
Command in Relation to Other Patterns 257
Summary 259
Chapter 25 Interpreter 261
An Interpreter Example 261
Interpreters, Languages, and Parsers 274
Summary 275
Part V Extension Patterns 277Chapter 26 Introducing Extensions 279
Principles of Object-Oriented Design 279
The Liskov Substitution Principle 280
The Law of Demeter 281
Removing Code Smells 283
Beyond Ordinary Extensions 283
Summary 285
Chapter 27 Decorator 287
A Classic Example: Streams and Writers 287
Function Wrappers 295
Decorator in Relation to Other Patterns 303
Summary 303
Chapter 28 Iterator 305
Ordinary Iteration 305
Thread-Safe Iteration 307
Iterating over a Composite 313
Summary 324
Chapter 29 Visitor 325
Visitor Mechanics 325
An Ordinary Visitor 327
Visitor Cycles 333
Visitor Risks 338
Summary 340
Part VI Appendixes 341Appendix A Directions 343
Get the Most from This Book 343
Understand the Classics 344
Weave Patterns into Your Code 344
Keep Learning 345
Appendix B Solutions 347Appendix C Oozinoz Source 427
Acquiring and Using the Source 427
Building the Oozinoz Code 427
Testing the Code with JUnit 428
Finding Files Yourself 428
Summary 429
Appendix D UML at a Glance 431
Classes 432
Class Relationships 433
Interfaces 435
Objects 436
States 437
Glossary 439Bibliography 447Index 449 