ABSTRACT
You know that on the Web, a user uses a browser, which is a thin client. Th e presentation for the user-facing interface is not created in the browser; rather, it is created on the server side and sent through Hypertext Transfer Protocol (HTTP) to the Web browser. Th e Web tier in fact is a presentation layer where the user interface is generated dynamically and presented to the user. In J2EE this is achieved by using Servlets and Java Server Pages (JSPs) running inside a Servlet container. Th e other tier that requires Java programming is the business tier where the business logic can be implemented using EJBs. Also the interaction between the JSPs, Servlets, and EJBs follow a design pattern called model-view-controller (MVC) architecture (Figure 9.2).
