Design Patterns in ABAP Objects - Koseoglu, Kerem

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Résumé :
Use design patterns to step up your object-oriented ABAP game, starting with MVC! Want to create objects only when needed? Call objects only when required, minimizing runtime and memory costs? Reduce errors and effort by only coding an object once? Future-proof your code with a flexible design? Design patterns are the answer! With this guide, you'll get practical examples for every design pattern that will have you writing readable, flexible, and reusable code in no time!Creational Design PatternsCreate objects with the abstract factor, builder, factory, lazy initialization, multiton, prototype, and singleton design patternsStructural Design PatternsAllow objects to interact and work together without interdependency with the adapter, bridge, composite, data access object, decorator, fa?ade, flyweight, property container, and proxy design patterns.Behavioral Design PatternsIncrease the flexibility of your object communication with the chain of responsibility, command, mediator, memento, observer, servant, state, strategy, template method, and visitor design patterns.Highlights:MVC (model, view, controller) patternSingleton patternFactory patternBuilder patternObserver patternVisitor patternLazy initialization patternTemplate methodStrategy patternDecorator patternABAP-specific examplesAnti-patterns...

Biographie:
Dr. Kerem Koseoglu is a freelance SAP software architect, working professionally since 2000. He specializes in the development of comprehensive applications using design patterns and also conducts technical training related to design patterns. He has participated in global software development projects, taking diverse roles including lead architect, team lead, developer, technical advisor, instructor, and project manager. His former publications include four books and countless articles for technical magazines in Turkey. He has a Ph.D. in organizational behavior.
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Sommaire:
... Preface ... 17

... Design Pattern Categories ... 19

... How to Learn ... 20

PART I ... Architectural Design Patterns ... 25

1 ... MVC ... 27

1.1 ... Case Study: Read, Process, Display, and Post ... 28

1.2 ... Passing Select Options ... 33

1.3 ... Distributing Application Logic ... 34

1.4 ... Related Patterns ... 34

1.5 ... Summary ... 35

PART II ... Creational Design Patterns ... 37

2 ... Abstract Factory ... 39

2.1 ... Case Study: Log Analysis ... 40

2.2 ... Related Patterns ... 47

2.3 ... Summary ... 47

3 ... Builder ... 49

3.1 ... Case Study: Jobs for Text Files ... 49

3.2 ... When to Use ... 66

3.3 ... Privacy ... 66

3.4 ... Summary ... 67

4 ... Factory ... 69

4.1 ... Case Study: FI Documents for Parties ... 69

4.2 ... Advantages ... 75

4.3 ... Related Patterns ... 75

4.4 ... Summary ... 76

5 ... Lazy Initialization ... 77

5.1 ... Case Study: Logging Errors ... 77

5.2 ... Advantages ... 81

5.3 ... Related Patterns ... 81

5.4 ... Summary ... 82

6 ... Multiton ... 83

6.1 ... Case Study: Vendor Balance ... 84

6.2 ... When to Use ... 88

6.3 ... When to Avoid ... 88

6.4 ... State Modification ... 89

6.5 ... Summary ... 89

7 ... Prototype ... 91

7.1 ... Case Study: Item Clone ... 91

7.2 ... Changing Class Properties ... 95

7.3 ... Clone Operations ... 96

7.4 ... Related Patterns ... 96

7.5 ... Summary ... 97

8 ... Singleton ... 99

8.1 ... Case Study: Subcomponents ... 99

8.2 ... Advantages and Disadvantages ... 106

8.3 ... Related Patterns ... 106

8.4 ... Summary ... 106

PART III ... Structural Design Patterns ... 107

9 ... Adapter ... 109

9.1 ... Case Study: Project Management Tools ... 109

9.2 ... Glue Code ... 118

9.3 ... Two-Way Adapters ... 118

9.4 ... Legacy Classes ... 122

9.5 ... Summary ... 122

10 ... Bridge ... 123

10.1 ... Case Study: Messaging Framework ... 123

10.2 ... Advantages ... 131

10.3 ... Summary ... 131

11 ... Composite ... 133

11.1 ... Recursive Programming: A Refresher ... 133

11.2 ... Case Study: HR Positions ... 137

11.3 ... Advantages ... 144

11.4 ... Disadvantages ... 144

11.5 ... When to Use ... 145

11.6 ... Related Patterns ... 145

11.7 ... Summary ... 146

12 ... Data Access Object ... 147

12.1 ... Case Study: Potential Customers ... 147

12.2 ... Redundant Code Prevention ... 152

12.3 ... Related Patterns ... 153

12.4 ... Summary ... 153

13 ... Decorator ... 155

13.1 ... Case Study: User Exit ... 155

13.2 ... Advantages and Challenges ... 161

13.3 ... Related Patterns ... 162

13.4 ... Summary ... 162

14 ... Fa?ade ... 165

14.1 ... Case Study: Bonus Calculation ... 166

14.2 ... When and Where to Use ... 168

14.3 ... Related Patterns ... 170

14.4 ... Summary ... 170

15 ... Flyweight ... 171

15.1 ... Case Study: Negative Stock Forecast ... 171

15.2 ... Disadvantages ... 181

15.3 ... When to Use ... 181

15.4 ... Related Patterns ... 182