USE CASE REALIZATIONS

1. USE CASE REALIZATIONS CIS 480, Spring 2012

2. Adding Stereotype Options • We need to add options (Controller and User Interface) to the stereotypes available for our classes • Click on the UML tab at the top of the page • Then Click on the Stereotypes Icon

3. Adding Sterotypes (Continued) • Click new on the Dialog box that appears, then • Type in the name under the Stereotype column and • Select Class under the Base Class Column

4. Class Diagram Update • Create a class Diagram for the classes involved in the target Use Case(s) • You can drag and drop the classes involved • Add a controller class (or more than 1 if needed) • Be sure to specify the Controller Stereotype when creating • Add visibility links showing which classes need to know about other classes • You can use the Dependency link symbol in the class model for this

5. Adding Methods to Domain Classes • For each of the domain classes add • Constructor method(s) • One constructor for each set of data that might be used to initially create an object of this class • Add Update methods (Think Property with a Set Method in C#) for each Attribute that users will be able to update • Add any additional methods that you know will be a responsibility of the class based upon the use case description

6. Adding Class Methods • You may add class method(s) to return an array of object instances of the class • E.G. the Professor class could have a getProfessors method that returns a set of professor IDs and Names • Alternatively, a separate collection class could be used for this.

7. Design Sequence Diagrams • You will create a sequence diagram for each use case in order to achieve the Use Case realizations described in your text. • Start by adding instances of the domain classes needed for the use case and its controller class • Leave room on the left side of the diagram for the actor and UI classes (to be added later) • Arrange you classes from left to right starting with the controller and then the 1st domain class accessed, etc.

8. Adding Messages • Review the Use Case Description • Determine what the controller needs to respond to the first user request • Add the set of messages and responses needed to achieve the needed response • Use existing methods (Operations) where they are available • Add new Operations when necessary (They will be automatically added as methods of the receiving object’s class)

9. SHOWING LOOPS ETC. • VISIO does not provide loop and alt frames that look like those in your text. • We will use the 2-Element Constraint link to designate Repetition (Loop) structures and • The Or Constraint link to designate if logic

10. Use the 2-element Constraint for Denoting Loops in your Design Level Sequence Diagram

11. Making name visible on 2-Element Constraint • The name of a 2-element constraint is not visible by default. • You will need to right click on this link and select Shape display options. • Then check the checkbox next to name on the dialog that appears & click OK

12. Adding Front End • Once the Business logic has been captured between the controller and domainn (entity) classes, • Add the actor and the user interface class(es) • Add appropriate messages. • Actor interacts only with User Interface Classes • User Interface Classes interact only with the Actor and with the Controller class.

13. ADDING DATA ACCESS CLASSES • We will not be adding the Data Access classes, but you should note that they would be add on to the right side of the diagram at this point. • Starting with the Controller and Domain classes 1sthelps with keeping the front end UI classes as cohesive and decoupled as possible.