Preface xvChapter 1: Introduction 1Tour Guide 3And Now... 4Chapter 2: Patterns 5Chapter 3: A Theory of Programming 9Values 10Principles 13Conclusion 18Chapter 4: Motivation 19Chapter 5: Class 21Class 22Simple Superclass Name 23Qualified Subclass Name 24Abstract Interface 24Interface 26Abstract Class 26Versioned Interface 27Value Object 28Specialization 31Subclass 32Implementor 34Inner Class 34Instance-Specific Behavior 36Conditional 36Delegation 38Pluggable Selector 40Anonymous Inner Class 41Library Class 41Conclusion 42Chapter 6: State 43State 44Access 45Direct Access 46Indirect Access 47Common State 47Variable State 48Extrinsic State 50Variable 50Local Variable 51Field 52Parameter 53Collecting Parameter 55Optional Parameter 56Var Args 56Parameter Object 57Constant 58Role-Suggesting Name 58Declared Type 60Initialization 61Eager Initialization 61Lazy Initialization 62Conclusion 62Chapter 7: Behavior 63Control Flow 64Main Flow 64Message 65Choosing Message 65Double Dispatch 66Decomposing (Sequencing) Message 67Reversing Message 67Inviting Message 68Explaining Message 69Exceptional Flow 70Guard Clause 70Exception 72Checked Exceptions 72Exception Propagation 73Conclusion 73Chapter 8: Methods 75Composed Method 77Intention-Revealing Name 79Method Visibility 80Method Object 82Overridden Method 83Overloaded Method 83Method Return Type 84Method Comment 85Helper Method 85Debug Print Method 86Conversion 87Conversion Method 87Conversion Constructor 88Creation 88Complete Constructor 89Factory Method 90Internal Factory 91Collection Accessor Method 91Boolean Setting Method 93Query Method 93Equality Method 94Getting Method 95Setting Method 96Safe Copy 97Conclusion 98Chapter 9: Collections 99Metaphors 100Issues 101Interfaces 103Implementations 107Collections 110Extending Collections 114Conclusion 115Chapter 10: Evolving Frameworks 117Changing Frameworks without Changing Applications 117Incompatible Upgrades 118Encouraging Compatible Change 120Conclusion 129Appendix A: Performance Measurement 131Example 131API 132Implementation 133MethodTimer 134Canceling Overhead 136Tests 136Conclusion 142Bibliography 145General Programming 145Philosophy 147Java 148Index 149