Software Evolution (eBook)

Tom Mens is professor at the Institute of Computer Science of the University of Mons-Hainaut in Belgium. He obtained his PhD in Science in 1999 at the Vrije Universiteit Brussel on the topic of software evolution. Being one of the leading researchers in this domain, he currently directs the ERCIM Working Group on Software Evolution. Serge Demeyer is professor at the University of Antwerp (Department of Mathematics and Computer Science), where he leads a research group investigating the theme of "Software Reengineering" (LORE - Lab On REengineering). His main research interest concerns software engineering (more precisely, reengineering of object-oriented software systems) but due to historical reasons he maintains a heavy interest in hypermedia systems as well. He is an active member of the corresponding international research communities, serving in various conference organization and program committees.

Foreword 6
Preface 8
Contents 12
List of Contributors 14
1 Introduction and Roadmap: History and Challenges of Software Evolution 18
1.1 The History of Software Evolution 18
1.2 Research Themes in Software Evolution 21
Part I Understanding and Analysing Software Evolution 29
2 Identifying and Removing Software Clones 30
2.1 Introduction 30
2.2 Software Redundancy, Code Cloning, and Code Duplication 31
2.3 Types of Clones 33
2.4 The Root Causes for Code Clones 34
2.5 Consequences of Cloning 36
2.6 Clone Evolution 38
2.7 Clone Management 39
2.8 Clone Detection 41
2.9 Comparison of Clone Detection Algorithms 43
2.10 Clone Presentation 46
2.11 Related Fields 49
2.12 Conclusions 50
3 Analysing Software Repositories to Understand Software Evolution 52
3.1 Introduction 52
3.2 An Overview of Software Repository Analysis 53
3.3 Release History 55
3.4 Software Evolution Analysis 61
3.5 Conclusion 81
4 Predicting Bugs from History 83
4.1 Introduction 83
4.2 What Makes a Module Defect-Prone? 85
4.3 Metrics 87
4.4 Problem Domain 90
4.5 Code Churn 96
4.6 Open Issues 98
4.7 Threats to Validity 100
4.8 Conclusion and Consequences 101
Part II Reengineering of Legacy Systems 103
5 Object-Oriented Reengineering 104
5.1 Introduction 104
5.2 Refactoring 105
5.3 Reengineering Patterns 111
5.4 Conclusion 117
6 Migration of Legacy Information Systems 118
6.1 Introduction 118
6.2 Migration Reference Model 124
6.3 The Transformational Approach 126
6.4 Schema Conversion 129
6.5 Data Conversion 134
6.6 Program Conversion 135
6.7 Tool Support 141
6.8 Industrial Application 144
6.9 Strategies Comparison 148
6.10 Conclusions 150
7 Architectural Transformations: From Legacy to Three-Tier and Services 152
7.1 Introduction 152
7.2 From Legacy Systems to Three-Tier Applications and Services 153
7.3 The Approach to Architectural Transformation 158
7.4 Implementation and Example 164
7.5 RelatedWork 175
Part III Novel Trends in Software Evolution 184
8 On the Interplay Between Software Testing and Evolution and its Effect on Program Comprehension 185
8.1 Introduction 185
8.2 Agile Software Development Methods 187
8.3 Program Comprehension 188
8.4 Test Smells and Refactorings 192
8.5 How Refactoring Can Invalidate Its Safety Net 196
8.6 Measuring Code and Test Code 205
8.7 Concluding Remarks 210
9 Evolution Issues in Aspect-Oriented Programming 215
9.1 Introduction 215
9.2 Aspect-Oriented Programming 218
9.3 Aspect Exploration 221
9.4 Aspect Extraction 228
9.5 Aspect Evolution 238
9.6 Summary 243
10 Software Architecture Evolution 245
10.1 Introduction 245
10.2 Component-Based Software Architecture: Concepts and Open Issues 246
10.3 Dynamic Software Architecture Description 250
10.4 Aspect-Oriented Architectures Description Language 254
10.5 The Safe Integration of New Concerns in a Software Architecture 257
10.6 RelatedWork 271
10.7 Conclusion 273
11 Empirical Studies of Open Source Evolution 275
11.1 Introduction 275
11.2 Empirical Studies of Open Source Evolution 282
11.3 Comparing the Evolution of Open and Closed Source Software Systems 293
11.4 Threats to Validity 294
11.5 Conclusions and Further Work 299
A Resources 302
B Glossary of Terms 306
C List of Acronyms 318
References 320
Index 351