To help understand the role of each of the technologies in the J2EE specification, a single case study will be followed throughout the daily exercises. As you work through the 21 days, a functional implementation of a simple enterprise application will be developed.
The chosen case study is a simple Job Agency. Jobs are categorized by Location and Skills required for the job. Customers advertise jobs, and Applicants register their location and skills so they can be matched to jobs. Customers and applicants will be notified of job matches by e-mail.
To illustrate the relationships between the different components in the data model for the Agency, a traditional database ERD diagram is shown in Figure 2.16.