Chapter 8 • Basic Systems Concepts and Tools 353
Use Case Name: Become Member
Actors: Browser
Goal: Enroll the browser as a new
member
Description: The Browser will be asked to
complete a membership form.
After the Browser submits
the application form, the
system will validate it and
then add the Browser to the
membership file and generate
a password that is e-mailed to
the Browser.
Pre-condition: The systems is up and the
Browser is logged in as
a guest
Post-condition: The Member password
e-mailed to the Browser/
Member is logged
Basic Flow
Actor action:
- This use case begins when
the Browser clicks the
membership button
- Browser completes and
submits the application
System response:
- Display the membership form
- Check for errors
- Check the membership database
for prior membership
- Create a password
- Add new or updated member
record to the membership
database
- Send an e-mail to the actor with
the password
The use case ends
Alternate Flow
Exception Flow
Prior membership handling
Errors in membership
application
5.1. Update membership record
5.2. Inform the browser
Continue from step 6 of Basic Flow
4.1. Identify errors
4.2. Return errors to Browser
Continue from step 4 of Basic Flow
4.3. Browser corrects errors
FIGURE 8.23 Become Member Use Case (Reprinted with permission from Chand, 2003)
- An extended relationship Use Case diagram to
logically model event flows beyond initial Use Case
requirements, showing alternatives and special cases
- A sequence diagram to capture the messages that
pass between object classes for a given Use Case
- A class diagram (similar to an entity-relationship
diagram) with each object’s attributes and methods as
well as a model of the relationships between object
classes that covers data used in all the use cases
Summary of Processes and Techniques
to Develop Information Systems
Yes, information systems development is very detailed,
and it is easy to become overwhelmed by the many
diagrams and documents. Why so detailed? The reason is
quality. Quality information systems support every
circumstance with repeatable, correct actions. Everyone
touched by the system has to agree on the business rules to
