Object Modeling
Session 6: Object Modeling
Preview
In the last session, you used data and process modeling techniques to develop a logical model of the new system. Now you will apply your object modeling skills to create various diagrams and documentation for the new TIMS system. You will review the background material and develop an object-oriented model that includes several types of diagrams.
Tasks
1. I need to review Jesse’s e-mail message regarding object modeling and the JAD session summary. I need to identify possible use cases and actors, and create a use case diagram for the TIMS system.
Possible use cases might include Student Payment, Register, Request Course, Teach Course, Determine Schedule, and Maintain Training Records. Possible actors might include Student, Instructor, Training Administrator, and Corporate Client. A sample use case diagram for Determine Schedule, Register, and Prepare Training Report follows:
2. She wants me to create a model of the use case that shows how students register. She also wants to see a class diagram.
A sample class diagram for the Register use case follows:
Student
Student number
Name
Address
SSN
Request course
Add course
Complete course
Drop course
Change student data
0..*
0..*
Registration Record
Student number
Course number
Payment method
Tuition due
Registers
Determine tuition
Prepare roster
Confirm
1..*
Includes
1..*
Course
Course number
Course name
Instructor
Day/Time
Add Course
Change Course
Delete Course
Instructor
Instructor ID
Name
Courses qualifications
Location
Phone
Teach course
Report outcome
Teaches
1..*
1
1
Updates
Training Record
Student number
Course number
Date
Completion data
Output to SCR staff
Output to student
Output to corporate client
3. I need to create a sample registration sequence diagram that shows the steps in the registration process.
Sample Registration Sequence Diagram:
Requests Course
Confirms Available
Schedules
Student
Registration
Courses
Checks Availability
Confirms
Notifies
Payment
Instructor
Bill
4. Jesse asked me to create a state transition diagram that describes typical student states and how they change based on certain actions and events. She said to include a brief cover memo.
Possible use cases might include Student Payment, Register, Request Course, Teach Course, Determine Schedule, and Maintain Training Records. Possible actors might include Student, Instructor, Training Administrator, and Corporate Client. A sample use case diagram for Determine Schedule, Register, and Prepare Training Report follows:
| RULES | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| Multiple courses? | Y | Y | Y | Y | N | N | N | N |
| Employed by SCR client? | Y | Y | N | N | Y | Y | N | N |
| Client service rep waiver? | Y | N | Y | N | Y | N | Y | N |
| Eligible for discount A | X | X | X | X | ||||
| Eligible for discount B | X | X | X | X | X | X | ||
| Not eligible for discounts | X |
Simplified rules:
| RULES | 1 | 2 | 3 | 4 | 5 | 6 |
| Multiple courses? | Y | Y | Y | N | N | N |
| Employed by SCR client? | Y | N | N | Y | N | N |
| Client service rep waiver? | – | Y | N | – | Y | N |
| Eligible for discount A | X | X | X | |||
| Eligible for discount B | X | X | X | X | ||
| Not eligible for discounts | X |
A sample decision tree follows:
Multiple courses
Client service rep override?
Not eligible for discounts
Eligible for discount B
Eligible for discount B
Eligible for discount A
Eligible for discount A and B
Eligible for discount A and B
Employed by SCR client?
Employed by SCR client?
Yes
Yes
No
No
Client service rep override?
No
No
Yes
Yes
No
Yes
Bills
Bills