Schaum's Outline Series

CHAPTER 8 Requirements 121
3. What functions are important to include in use case diagrams?
The important functions are those critical functions that convey the required functionality.
4. What criteria should be used to evaluate scenarios?
Every significant sequence of functions needs to be shown from the user’s point of view.
5. What criteria should be used to evaluate state diagrams?
State diagrams need to show all possible transitions. Every arc in the diagram needs to
have an event that caused the transition. There must also be a path from the start node
to every node and from every node to a terminal node.
6. What is the advantage of a system diagram?
Being less formal, it can be more flexible in expressing ideas about the overall system.
7. What can be a major problem with system diagrams?
The lack of formality can lead to ambiguous diagrams with one symbol being used for
different ideas.
Answers to Problems
1. Draw an object model for the B&B problem (see Problem 4.3).
See Fig. 8-8.
2. Draw an object model for the dental office problem (see Problem 4.2).
See Fig. 8-9.
customer
make res.
cancel
arrive
check out
B&B
reservation
date
Fig. 8-8. B&B object model.
date