* Creating a set of objects that share the responsibilities
implied by what a user needs to do.
Process= iterate the following
- SSD ->
- System Operations/events ->
- Contracts ( + tests ) ->
- Interactions & Classes ->
- UserInterface generates SystemEvents.
- SystemEvents feed the Controlers
- Controlers talk to each other and domain layer objects.
- Controlers return results to the UserInterface.
- Domain layer objects use lower layers as needed
- Domain layer objects notify the controlers if anything important happens.
[ patterns.html#MVC ]
Stock taking at a depot (bring the handed out answers
to the last quiz to class.
We use the
Design Class Diagram or DCD
to gather the functions/operations discovered in all the interactions
we study into a single collection of classes.
Interactions show objects. DCDs show classes.
An interaction that shows [a:A] sending a message f(x) to object [b:B]
will require the function/operation f(x) to be in class [B]. A message
from [c:C] to [d:B] will also go into class [B]. The objects
b and d are different objects in the same class.
All the messages in your interaction diagrams must appear in the targetted
classes in your DCD.
All the classes in your DCD should be the same as messages some interactions.
Check the spelling, naming, and parameters of each interaction message
with its matching DCD operation.
|When to design it?||LAST
|How to design it?||Start another use case.
|What objects are created first?||THINK