Appendix a Review Questions Solutions

Appendix A Review Questions Solutions

1. Compare and contrast the object-oriented analysis and design models with structured analysis and design models.

The biggest difference between the models is that the object-oriented models build on each other and are consistent. Models developed during structured analysis and design are weakly connected and lack a common representation.

2. Give an example of an abstract use case. Your example should involve at least two other use cases and show how they are related to the abstract use case.

In Figure A–2, the Track Sales and Inventory Data use case is an example of an abstract use case.

3. Explain the use of association role for an association on a class diagram.

The association role is the end of an association where it connects to a class. The role can be explicitly named, indicating the role played by the class attached to the end at which the name appears. A role will have multiplicity; multiplicity gives an indication of how many objects participate in the relationship.

4. Give an example of generalization. Your example should include at least one superclass and three subclasses, and a minimum of one attribute and one operation for each of the classes. Indicate the discriminator and specify the semantic constraints among the subclasses.

A suggested answer is provided below

5. Give an example of aggregation. Your example should include at least one aggregate object and three component objects. Specify the multiplicities at each end of all the aggregation relationships.

One example of aggregation is a vehicle. A car will have front and side air bags, an air conditioner, an engine, and other components. A suggested diagram is provided below.

6. Give an example of state transition. Your example should show how the state of the object undergoes a transition based on some event.

A suggested answer is provided below.