Implementation Patterns

Description

• Copyright 2008
• Pages: 176
• Edition: 1st

• EPUB (Watermarked)
• ISBN-10: 0-13-270255-X
• ISBN-13: 978-0-13-270255-3

Software Expert Kent Beck Presents a Catalog of Patterns Infinitely Useful for Everyday Programming

Great code doesn’t just function: it clearly and consistently communicates your intentions, allowing other programmers to understand your code, rely on it, and modify it with confidence. But great code doesn’t just happen. It is the outcome of hundreds of small but critical decisions programmers make every single day. Now, legendary software innovator Kent Beck—known worldwide for creating Extreme Programming and pioneering software patterns and test-driven development—focuses on these critical decisions, unearthing powerful “implementation patterns” for writing programs that are simpler, clearer, better organized, and more cost effective.

Beck collects 77 patterns for handling everyday programming tasks and writing more readable code. This new collection of patterns addresses many aspects of development, including class, state, behavior, method, collections, frameworks, and more. He uses diagrams, stories, examples, and essays to engage the reader as he illuminates the patterns. You’ll find proven solutions for handling everything from naming variables to checking exceptions.

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Sample Content

Table of Contents

Preface  xv

Chapter 1: Introduction  1

Tour Guide  3

And Now...  4

Chapter 2: Patterns  5

Chapter 3: A Theory of Programming  9

Values  10

Principles  13

Conclusion  18

Chapter 4: Motivation  19

Chapter 5: Class  21

Class  22

Simple Superclass Name  23

Qualified Subclass Name  24

Abstract Interface   24

Interface  26

Abstract Class  26

Versioned Interface  27

Value Object  28

Specialization  31

Subclass  32

Implementor  34

Inner Class  34

Instance-Specific Behavior  36

Conditional  36

Delegation  38

Pluggable Selector  40

Anonymous Inner Class  41

Library Class  41

Conclusion  42

Chapter 6: State  43

State  44

Access  45

Direct Access  46

Indirect Access  47

Common State  47

Variable State  48

Extrinsic State  50

Variable  50

Local Variable  51

Field  52

Parameter  53

Collecting Parameter  55

Optional Parameter  56

Var Args  56

Parameter Object  57

Constant  58

Role-Suggesting Name  58

Declared Type  60

Initialization  61

Eager Initialization  61

Lazy Initialization  62

Conclusion  62

Chapter 7: Behavior  63

Control Flow  64

Main Flow  64

Message  65

Choosing Message  65

Double Dispatch  66

Decomposing (Sequencing) Message  67

Reversing Message  67

Inviting Message  68

Explaining Message  69

Exceptional Flow  70

Guard Clause  70

Exception  72

Checked Exceptions  72

Exception Propagation  73

Conclusion  73

Chapter 8: Methods  75

Composed Method  77

Intention-Revealing Name  79

Method Visibility  80

Method Object  82

Overridden Method  83

Overloaded Method  83

Method Return Type  84

Method Comment  85

Helper Method  85

Debug Print Method  86

Conversion  87

Conversion Method  87

Conversion Constructor  88

Creation  88

Complete Constructor  89

Factory Method  90

Internal Factory  91

Collection Accessor Method  91

Boolean Setting Method  93

Query Method  93

Equality Method  94

Getting Method  95

Setting Method  96

Safe Copy  97

Conclusion  98

Chapter 9: Collections  99

Metaphors  100

Issues  101

Interfaces  103

Implementations  107

Collections  110

Extending Collections  114

Conclusion  115

Chapter 10: Evolving Frameworks  117

Changing Frameworks without Changing Applications  117

Incompatible Upgrades  118

Encouraging Compatible Change  120

Conclusion  129

Appendix A: Performance Measurement  131

Example  131

API  132

Implementation  133

MethodTimer  134

Canceling Overhead  136

Tests  136

Conclusion  142

Bibliography  145

General Programming  145

Philosophy  147

Java  148

Index  149

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