The Web model specifies the definitions of the Web components. The Web components serve HTML content to the user. Each component serves a subset of the classes and associations of the system. Extra details are added to the Web model to define the layout and the user interactions of the HTML pages. In this example, the Web components serve the same classes as in the data schemas of the entity beans.
Web components are defined similarly to EJB components. The served classes and associations are defined in Web data schemas similar to the EJB data schemas. The most important differences are:
The Web data schemas define which information is shown that can be altered by the user. One Web data schema is typically presented to the user in more than one HTML page. A user may create, query, alter, and delete objects from the domain. Which changes the user may execute is defined in properties of the elements of the Web data schemas.
5.3.1 The Transformation Rules
The rules for generating the Web application model from the UML model are almost equal to the ones for generating the EJB application model. Again, we will leave out the words UML and Web whenever the source and target model are clear.
Figure 5-4 depicts the Web model generated from the same PIM classes as the EJB model shown in Figure 5-3.
Figure 5-4. Web component model of Rosa's Breakfast Service