1. 1 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com An Introduction to Object-Oriented Analysis Objects and UML in plain English. Chapter 2: Systems Development and the Software Crisis Based on the book by David William Brown Based on the book by David William Brown John Wiley & Sons, ISBN 0471371378

2. 2 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com Copyright Copyright 8 2002 Flying Kiwi Productions All rights reserved. This slide presentation is based on “An Introduction to Object- Oriented Analysis; Objects and UML in Plain English,” by David William Brown, Wiley, ISBN 0471371378, “The Book.” Permission is hereby granted to copy, modify or excerpt all or any part of this slide presentation, provided it is solely for use with courses, seminars or other presentations or productions where a copy of The Book is purchased by or for each and every participant or recipient. An instructor guide is available from the publisher for such presentations.

3. 3 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com Chapter 2 Systems Development and the Software Crisis  Brief History  Need for a New Approach  Costs and Benefits of Objects

4. 4 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com  Brief History l 1950s and 1960s, Systems Analysis was unstructured, unorganized l It was not done well. l Over the last 30 years we have made many improvements But software still has just as many bugs! But software still has just as many bugs! But back then a large project was a few thousand lines of code But back then a large project was a few thousand lines of code Nowadays large means several million lines of code. Nowadays large means several million lines of code.

5. 5 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com  Brief History Maintenance changes have always been a problem.

6. 6 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com  Brief History l Backlogs At any time there has been about a 5-year backlog At any time there has been about a 5-year backlog Plus there has also been a 5-year invisible backlog. Plus there has also been a 5-year invisible backlog. l This has had two effects: n A move to end-user computing n A constant search for better ways to develop software systems.

7. 7 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com  Brief History l Reliability n What caused all the maintenance and backlogs? l Poor initial design led to problems of n Flexibility, the ability of a system to handle unforeseen events or transactions n Resilience, the ability to handle changes during maintenance without other problems happening with every little change.

8. 8 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com  Need for a New Approach to Systems Development l Many business managers do not realize how complex software development can be l Many use amateurs and hackers l Others hire out-of-date “professionals” l There are good ways and bad ways to do it l Good consultants are expensive l Because that’s what they are worth in ROI (Return on Investment) l Robin Williams’ new movie...

9. 9 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com “The Dead COBOL Programmers’ Society.”

10. 10 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com  Costs and Benefits of Objects Benefits of Objects: n System Stability n Maintainability n Reusable software components n Reality-based systems n Data accessibility n User involvement and ownership

11. 11 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com  Costs and Benefits of Objects Costs of Objects: n Installed software base s COBOL  Legacy Systems: Out-of-date systems that already exist and must continue to exist for the foreseeable future. n Retraining s Not just a new language, but s A whole new way of thinking n Need a carefully-planned conversion s See Chapter 15, “Moving to O-O Techniques”

12. 12 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com End of Chapter 2.

13. 13 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com End of Chapter 2.

14. 14 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com End of Chapter 2.

15. 15 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com

16. 16 Copyright 8 2002 Flying Kiwi Productions Inc. flykiwi@home.com