Most developers adopt MVC for developing applications in J2EE, at the application level MVC ( Model View Control ) would mean
View – Presentation Layer ( JSP, Servlet, CSS, HTML , AJAX etc )
Control – Business Logic ( EJB, MDB ( JMS) etc)
Model – Persistance layer ( DB, XML etc )
In J2EE Presentation layer we again follow MVC. here MVC is would be
View – The UI aka the screen, here we are worried about formatting data in a presentable way to the user ( JSPs, CSS, and taglibs like the JSTL)
Model – The model is the data. In a “View Cars” screen, the model is a Plain Old Java Object (POJO) or a simple Java Bean
Control – The controller mediates communication between the View and the Model. If a request comes in, it retrieves the Java Beans from the persistence layer and hands them to the view. In a web application, the controller generally is a servlet.
Most of the popular presentation layer frameworks such as Struts, JSF, Webwork or Tapestry adopt similar philosophies, they differ in Implementation.
Reference – “Java at Work A Practicle Guide” a OReally Book