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Most of the technical stuff that happens in the View component of the MVC-2 Architecture is hidden by java Server Faces, which provides a Component-Based Architecture for designing reusable User Interface Components.

The framework not only allows for the creation of customized User Interface Components, but it also supports a number of advanced features such as event handling, validating user inputs given by clients, and easy page navigation.

The advantage of Java Server Faces is that there is very little connectivity between the UI Components that represent the various behaviors/properties and the Rendering.
In fact, it's practically none. As a result, HTML browsers aren't the only client apps that can be used. WML Browsers function nicely with JSF Applications.