1 slc5 TTYP – C++ revisited 1 Which of the following statements are reasonable after the following statement: char* fred = new char[5]; a. fred = bill; b. strcpy(fred, “store”); c. strcpy(“store”,fred); d. fred = “store”;

2 slc5 TTYP – C++ revisited 2 Which statements are reasonable immediately after the following statement? : char* max; a. max = “fred”; b. max = new char[10]; c. max = 0;

3 slc5 Scenarios, Use Cases, Interactions u The lab this week will cover creating use case diagrams and interaction diagrams in Rational Rose

4 slc5 Use Case Diagram u Draw important actors u Add each action

5 slc5 Scenarios u A description of a sequence of actions

6 slc5 Draw Interaction Diagrams u Vertical lines for the classes u Use scenario to put in function calls

7 slc5 TTYP – interaction diagram u Draw a interaction diagram for checking out a book

8 slc5 Software Development Software Crisis, Software Quality and the Software Life Cycle Pressman pp 1-52

9 slc5 Software Crisis u Software is delivered over-budget, late, and not correct –software complexity –programmer productivity u DeMarco’s (IEEE Software Apr 94) –only too costly because they would like to pay less –only late because they want it sooner

10 slc5 Future of Software u increasing complexity u increasing criticality u trends –more formalisms –object-oriented –Reuse, COTS, and components –software measurement –emphasis on quality

11 slc5 Quality - the ultimate goal Software that does what it is suppose to or I will know it when I see it

12 slc5 How to achieve quality u Top-down –through software life cycle –through quality improvement –see Dilbert u Bottom-up –Personal Software Process

13 slc5 Software Life Cycle (SLC) formalizing the process of software development Pr:22-53

14 slc5 Waterfall Model

15 slc5 Waterfall u Royce u first realization that there was a standard sequence of tasks u useful as a management tool –milestones u maybe too restrictive

16 slc5 Software vs Houses u Requirements u Design u Implementation u Maintenance u Schematic u Blueprints u Building House u Home Repairs

17 slc5 Requirements u Phases –Preliminary Analysis –Market Analysis –Requirements Specification u Documents –Statement of Work (SOW) –Requirement Specification (SRS) »Data Flow Diagram »Data Specification –User Manual, Test Plans, SQA Plans

18 slc5 Design u Phases –Architectural Design –Detailed Design u Documents –Hierarchy Diagram –Module Specification –PDL

19 slc5 Implementation u Phases –coding –unit testing –integration –acceptance –delivery u Documents –code –test reports –final user manual

20 slc5 Maintenance u Tasks –error correction –enhancement –version control –regression testing –version release u Documents –error report –test reports –revised documentation

21 slc5 Waterfall Alternatives u Rapid Prototyping u Spiral Model u Incremental Development u RUDE

22 slc5 Rapid Prototyping u Build a throw-away version –test concepts –test requirements –not complete functionality u Saves developing wrong product u Saves developing unnecessary features

23 slc5 Spiral Model u Boehm (IEEE Computer May88) u Revisit the basic tasks of –determine objectives –evaluate alternatives –develop –plan next phase u uses prototypes

24 slc5 Incremental u Parnas (IEEE TOSE Mar79) u Design minimal subset u Design minimal increments u Always able to deliver something useful

25 slc5 RUDE - the AI approach u Run u Understand u Debug u Enhance