Learn Java for Web Development

154 CHAPTER 3: Best Practices in Java EE Web Development

Front Controller

The front controller does the following:

   Centralizes request processing

   Delegates to the view using the dispatcher

   Uses the view helper to separate the business logic concerns from the

presentation logic concerns

Dispatcher

The dispatcher does the following:

   Is responsible for view management and navigation

   Delegates to the view

   Uses a helper to push data into the view

Helper

The helper does the following:

   Helps the view or the controller to complete its processing

View

The view does the following:

   Represents and displays information to the client

   Pulls the data from the data source using a view helper

Figure 3-16 illustrates the sequence diagram of the Dispatcher View pattern.