1. Senior Project II Team 1 – Class Diagram
By Hiroko Boehnlein & Kyle Walters

2. Where we started! Step 1. Identify potential objects.
Step 2. Choose from the proposed objects.
Step 3. Identify associations and multiplicity.
Step 4. Identify generalizations/specialization relationships
Step 5. Identify aggregation relationships.
Step 6. Identify boundary classes.
Step 7. Identify control classes.
Step 8. Create the class diagram.

3. Step 1 (1) Identified potential objects.
This was accomplished by reviewing our use cases, and finding nouns which correspond to entities or events.
If necessary you can add each noun to a list of potential objects, which will be used in Step 2.

4. Step 2 (2) Choose from the proposed objects.
Not all objects are suitable objects. We will need to eliminate objects that are:
Synonyms.
Nouns outside the scope of the system.
Nouns that are roles without unique behavior or are external roles.
Unclear nouns that need focus.
Nouns that really actions or attributes.
Now we have identified our system objects.

5. Step 3 (3) Identify associations and multiplicity.
Now we will need to identify associations that exist between objects/classes.
An association is what a object/class “needs to know” about the other object/class, this allows the for a object class to cross-reference another object.
After the association is identified, the multiplicity which governs the association must be defined.

6. Step 4 (4) Identify generalization/specialization relationships.
Now we need to determine if any generalization/specialization relationships exist.
This relationship is a classification hierarchies or “is a” relationships, and consists of superobjects and subobjects.
Superobjects contain common attributes and behaviors of the hierarchy.
Subobjects are specialized because they contain attributes and behavior unique to that object, but also inherit the superobjects attributes and behaviors.

7. Step 5 (5) Identify aggregation relationships.
We must now determine if any aggregation relationships exist.
Aggregation relationships are where one object “is part of” another object; sometimes referred to as a whole/part relationship.
Aggregation relationships do not imply inheritance.

8. Step 6 (6) Identify boundary classes.
We must now identify boundary classes.
User interface boundary classes facilitate communication with human users of the system.
*Menus, forms, etc.
System interface boundary classes facilitate communications with other systems.
These boundary classes are responsible for managing the dialogue with the external system, like getting data from an existing database system or flat file…
Provides an interface to that system for this system.

9. Step 7 (7) Identify control classes.
We must now identify control classes.
A Control Class is a class used to model control behavior specific to one or more use cases.
Control classes encapsulate use-case-specific behavior.
Control classes provide coordinating behavior in the system.

10. Step 8 (8) Create the class diagram.
Now we will implement the class diagram.
You will want to use you favorite modeling program such as: System architect or Rational Rose, and have hours of fun designing you beautiful class diagram!

11. Class Diagram