1. Sub-Phase Low Level Design (cont)

2. More UML – Class Diagram
Method Syntax
[visibility] name [(parameter-list)] [: return-type]
[visibility] [(parameter-list)]
+ means public name of parameter + type
- means private void is default
# means protected
NOTE: the square brackets indicate that their contents are optional, the square brackets should not be included on your class diagram
Janice Regan, 2008

3. More UML – Class Diagram
Attribute Syntax
[visibility] name [multiplicity] [: type]
[= initial-value] [{property-string}]
[visibility] [{property-string}]
+ means public changeable - default
- means private frozen - constant
# means protected
NOTE: the square brackets indicate that their contents are optional, the square brackets should not be included on your class diagram
Janice Regan, 2008

4. Updating classes
Should use all parts of the syntax provided on the previous two slides in your class diagram. The exception is when one of the fields is not appropriate to the attribute or method being described
E.g. No parameters given indicates there are none
We have discovered attributes and methods for each class now we need to fill in the information to give a full description in our class diagram
Need data types
Need to determine visibility of methods (should have parameter lists already)
Janice Regan, 2008

5. Patron and Resource class attributes
+Name:String
+Address:String
+Phone # :String
+Patron ID: integer
+List of borrowed resources[0..24]:Long[ ]
. . .
+get ExpiryDate( ) : Date
+getName( ) : String
+checkIn(call# : integer)
Janice Regan, 2008

6. Validation & Verification: Class Design
All requirements developed during analysis must be addressed during design
All design documents and diagrams must cross reference fcn requirements from the requirements specification
Verification:
Design diagrams created by diff. software developers
To ensure all pieces fit together: Informal walk-through
Run through each scenario, following diagrams
Ensure that messages use method signature correctly
Janice Regan, 2008

7. Summary of Low Level Design
Refine scenarios from refined use cases created during Requirement Analysis and refined during High Level Design
Refine class diagrams by adding attribute details from class diagrams created for each use case in Requirement Analysis, and refined scenarios produced in the above step
For each refined scenario, develop interaction diagrams: collaboration or sequence diagrams
Further refine class diagrams by adding methods these methods are implied from the inter-object communication conveyed in the scenarios' interaction diagrams
Define algorithm for each method
Janice Regan, 2008