Introduction. O.Univ.-Prof. DI Dr. Wolfgang Pree. Universität Salzburg

Transcription

1 OO Reengineering Patterns O.Univ.-Prof. DI Dr. Wolfgang Pree Universität Salzburg Introduction 2

2 Goals Convince you about the following: 3 Lehman s laws 4

3 What is a legacy system? 5 Software maintenance 6

4 What about OO? 7 Definitions 8

5 Reverse and reengineering 9 Goals of reverse engineering 10

6 Reverse engineering techniques 11 Goals of reengineering 12

7 Reengineering techniques 13 Architectural problems 14

8 Refactoring opportunities 15 Tool integration 16

9 Tool integration overview 17 Why integrate tools? 18

10 Which tools to integrate? 19 Tool integration issues 20

11 Basic tool architecture 21 Help yourself approach build your own parser translate between file formats communicate via APIs collect execution traces 22

12 Exchange standards 23 Reference format 24

13 Openness 25 Meta models 26

14 UML shortcomings 27 Conclusion 28

15 Design extraction 29 extreme situation 30

16 Goals 31 What is design? 32

17 Why design extraction is needed? 33 Small example straighten UML reverse engineered diagrams (I) 34

18 Small example straighten UML reverse engineered diagrams (II) 35 Small example straighten UML reverse engineered diagrams (III) 36

19 Small example straighten UML reverse engineered diagrams (IV) 37 Essential questions when interpreting UML 38

20 Levels of interpretation: perspectives 39 Attributes in perspectives 40

21 Operations in perspectives 41 Associations 42

22 Associations conceptual perspective 43 Associations specification perspective 44

23 Arrows navigability 45 Generalization 46

24 Need for a clearer mapping 47 Meanings of private 48

25 class method inheritance 49 Stereotypes to extend UML 50

26 Instance/class associations 51 Association extractions (I) 52

27 Association extractions (II) 53 Operation extractions (I) 54

28 Operation extractions (II) 55 Design patterns as documentation elements? 56

29 Evolution impact analysis: reuse contract 57 Example 58

30 Reuse contracts general idea 59 Example 60

31 Documenting dynamic behavior 61 UML sequence diagrams 62

32 Implications 63 Conclusions 64

33 Metrics for OO reengineering 65 Outline 66

34 Why metrics in OO reengineering? 67 Which metrics to collect? 68

35 Assumptions 69 Definitions 70

36 Results: problem detection 71 Results: stability assessment 72

37 Results: reverse engineering 73 Split into superclass/merge with superclass 74

38 Split into subclass/merge with subclass 75 Move to superclass/subclass or sibling class 76

39 Split method/factor common functionality 77 Conclusions 78

40 Refactoring 79 Outline 80

41 Why refactoring? 81 Iterative development life cycle 82

42 What is refactoring? 83 Which refactoring tools? 84

43 Case study: Internet banking initial requirements 85 Prototype design 86

44 Prototype design of contracts 87 Prototype implementation 88

45 Prototype consolidation 89 Expansion 90

46 Expanded design 91 Expanded design: contracts 92

47 Expanded implementation 93 Consolidation: problem detection 94

48 Consolidation: refactored class diagram 95 Refactoring sequence (I) 96

49 Refactoring sequence (II) 97 Refactoring sequence (III) 98

50 Refactoring sequence (IV) 99 Refactoring sequence (V) 100

51 Tool support 101 Conclusion (I) 102

52 Conclusion (II) 103 Bibliography 104

53 Annotated biliography (I) 105 Annotated biliography (II) 106

54 Annotated biliography (III) 107 References (I) 108

55 References (II) 109 References (III) 110

56 References (IV) 111 References (V) 112