4.8 Summary

As a medium, the Web requires application developers to create user interfaces that are flexible and easy to maintain. Web applications can be made more flexible and maintainable through the use of J2EE component technologies such as servlets and JavaServer Pages which used to generate dynamic content in a portable and scalable manner.

Enterprise Web applications should be developed using modular components. These components include servlets, JSP pages, JavaBeans components, and tag libraries containing custom tags. Depending on the composition of your development team, time constraints, and application architecture, the use of JSP pages and servlets will differ. Both technologies have merits and should be used accordingly.

Internationalization expands the potential user base of a Web application. A properly internationalized application can be quickly localized for any number of languages without modifications to the code. It is much easier to internationalize an application during the design phase at the beginning of a development cycle. Retrofitting an existing application can be difficult and expensive.

Architectures for Web applications include basic JSP pages and servlets, Web-centric applications that use JSP pages with modular components, and EJB-centric applications that use JSP pages with enterprise beans. A Web-centric application can be migrated to a highly manageable, scalable, modular, EJB-centric application by using the steps described in this chapter. Gradual migration to a more complex design is less risky than making large-scale design changes to an application.