tailieunhanh - Seventh Edition - Chương 2

Tham khảo tài liệu 'seventh edition - chương 2', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Object-Oriented and Classical Software Engineering Seventh Edition, WCB/McGraw-Hill, 2007 Stephen R. Schach srs@ CHAPTER 2 SOFTWARE LIFE-CYCLE MODELS Overview Software development in theory Winburg mini case study Lessons of the Winburg mini case study Teal tractors mini case study Iteration and incrementation Winburg mini case study revisited Risks and other aspects of iteration and incrementation Managing iteration and incrementation Other life-cycle models Comparison of life-cycle models Software Development in Theory Ideally, software is developed as described in Chapter 1 Linear Starting from scratch Figure Software Development in Practice In the real world, software development is totally different We make mistakes The client’s requirements change while the software product is being developed Winburg Mini Case Study Episode 1: The first version is implemented Episode 2: A fault is found The product is too slow because of an implementation fault | Object-Oriented and Classical Software Engineering Seventh Edition, WCB/McGraw-Hill, 2007 Stephen R. Schach srs@ CHAPTER 2 SOFTWARE LIFE-CYCLE MODELS Overview Software development in theory Winburg mini case study Lessons of the Winburg mini case study Teal tractors mini case study Iteration and incrementation Winburg mini case study revisited Risks and other aspects of iteration and incrementation Managing iteration and incrementation Other life-cycle models Comparison of life-cycle models Software Development in Theory Ideally, software is developed as described in Chapter 1 Linear Starting from scratch Figure Software Development in Practice In the real world, software development is totally different We make mistakes The client’s requirements change while the software product is being developed Winburg Mini Case Study Episode 1: The first version is implemented Episode 2: A fault is found The product is too slow because of an implementation fault Changes to the implementation are begun Episode 3: A new design is adopted A faster algorithm is used Episode 4: The requirements change Accuracy has to be increased Epilogue: A few years later, these problems recur Evolution-Tree Model Winburg Mini Case Study Figure Waterfall Model The linear life cycle model with feedback loops The waterfall model cannot show the order of events Figure Return to the Evolution-Tree Model The explicit order of events is shown At the end of each episode We have a baseline, a complete set of artifacts (constituent components) Example: Baseline at the end of Episode 3: Requirements1, Analysis1, Design3, Implementation3 Lessons of the Winburg Mini Case Study In the real world, software development is more chaotic than the Winburg mini case study Changes are always needed A software product is a model of the real world, which is continually changing Software professionals are human, and therefore make mistakes Teal Tractors Mini Case Study