TABLE OF CONTENTS i CHAPTER 9 DESIGN CONCEPTS 156 9.1 Design Within the Context of Software Engineering 157 9.2 The Design Process 159 9.2.1 Software Quality Guidelines and Attributes 160 9.2.2 The Evolution of Software Design 161 9.3 Design Concepts 163 9.3.1 Abstraction 163 9.3.2 Architecture 163 933 Patterns 164 9.3.4 Separation of Concerns 165 9.3.5 Modularity 165 936 Information Hiding 166 937 Functional Independence 167 9.3.8 Stepwise Refinement 16 9.3.9 Refactoring 168 9.3.10 Design Classes 169 9.4 The Design Model 171 9.4.1 Design Modeling Principles 173 9.4.2 Data Design Elements 174 9.43 Architectural Design Elements 175 9.4.4 Interface Design Elements 175 9.4. Component-Level Design Elements 176 9.46 Deployment-Level Design Elements 177 9.5 Summary 178 CHAPTER 10 ARCHITECTURAL DESIGN- A RECOMMENDED APPROACH 181 101 Software architecture 182 10.1.1 What Is Architecture?182 10.1.2 Why Is Architecture Important? 183 10.1.3 Architectural Descriptions 183 10.1.4 Architectural Decisions 184 10.2 Agility and Architecture 185 10.3 Architectural Styles 186 10.3.1 A Brief Taxonomy of Architectural Styles 187 10.3.2 Architectural Patterns 192 10.3.3 Organization and Refinement 193TABLE OF CONTENTS xiii CHAPTER 9 DESIGN CONCEPTS 156 9.1 Design Within the Context of Software Engineering 157 9.2 The Design Process 159 9.2.1 Software Quality Guidelines and Attributes 160 9.2.2 The Evolution of Software Design 161 9.3 Design Concepts 163 9.3.1 Abstraction 163 9.3.2 Architecture 163 9.3.3 Patterns 164 9.3.4 Separation of Concerns 165 9.3.5 Modularity 165 9.3.6 Information Hiding 166 9.3.7 Functional Independence 167 9.3.8 Stepwise Refinement 167 9.3.9 Refactoring 168 9.3.10 Design Classes 169 9.4 The Design Model 171 9.4.1 Design Modeling Principles 173 9.4.2 Data Design Elements 174 9.4.3 Architectural Design Elements 175 9.4.4 Interface Design Elements 175 9.4.5 Component-Level Design Elements 176 9.4.6 Deployment-Level Design Elements 177 9.5 Summary 178 CHAPTER 10 ARCHITECTURAL DESIGN— A RECOMMENDED APPROACH 181 10.1 Software Architecture 182 10.1.1 What Is Architecture? 182 10.1.2 Why Is Architecture Important? 183 10.1.3 Architectural Descriptions 183 10.1.4 Architectural Decisions 184 10.2 Agility and Architecture 185 10.3 Architectural Styles 186 10.3.1 A Brief Taxonomy of Architectural Styles 187 10.3.2 Architectural Patterns 192 10.3.3 Organization and Refinement 193