1. Analysis into Design

2. Specifying Business Rules Identifying necessary constraints in an organisation’s operations Can apply to structured or semi-structured decisions Often expressible as IF …. THEN …. ELSE statements

3. Examples of business rules IF customer owes money THEN no further transactions are accepted. IF borrower has 6 books out THEN no further loans are permitted. IF postgrad student has 180 credits THEN he/she has achieved an MSc degree

4. Ways of addressing business rules in a system design Forms and multiplicity of associations on Class Diagrams Separate text boxes on diagrams Calculated fields within database queries or validation rules.

5. Ways of specifying business rules Decision tables - ensure all possibilities are covered. Structured English - program-like expression of the rule’s logic Flow charts Object Constraint Language (OCL) Activity diagrams

6. Drawing Activity Diagrams Purpose –to model a task (for example in business modelling) –to describe a function of a system represented by a use case –to describe the logic of an operation –to model the activities that make up the life cycle in the Unified Process

7. Notation of Activity Diagrams Activities –rectangle with rounded ends –meaningful name Transitions –arrows with open arrowheads Add a New Client Assign Staff Contact

8. Notation of Activity Diagrams Start state –black circle Decision points –diamond Guard conditions –in square brackets Final state –black circle in white circle [campaign to add] [no campaign to add] Add a New Client Assign Staff Contact Add New Campaign

9. Notation of Activity Diagrams Swimlanes –vertical columns –labelled with the person, organisation or department responsible for the activities in that column Record Completion of a campaign Issue invoice Campaign Manager ClientAccountant Pay invoice Record client payment

10. Patterns in Analysis and Design Common arrangements of objects to address similar problems in different situations (aids reuse) Can be applied at program or organisational level Issue for organisational level - what is the nature of relations between classes?

11. Example: patterns for modelling organisation structures Fowler argues this is not a very reusable pattern because it does not allow for organisational change

12. A better pattern - more reusable

13. Other examples of patterns at organisational level Measurement-diagnosis pattern: applied by Fowler to clinical treatment and business finances Client-entitlement accumulation: similar pattern in, e.g., university student records and book clubs Objective - produce something that is generalisable, not specific