type=page
status=published
title=JavaServer Faces Technology Benefits
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JavaServer Faces Technology Benefits
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[[BNAPJ]]

[[javaserver-faces-technology-benefits]]
JavaServer Faces Technology Benefits
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One of the greatest advantages of JavaServer Faces technology is that it
offers a clean separation between behavior and presentation for web
applications. A JavaServer Faces application can map HTTP requests to
component-specific event handling and manage components as stateful
objects on the server. JavaServer Faces technology allows you to build
web applications that implement the finer-grained separation of behavior
and presentation that is traditionally offered by client-side UI
architectures.

The separation of logic from presentation also allows each member of a
web application development team to focus on a single piece of the
development process and provides a simple programming model to link the
pieces. For example, page authors with no programming expertise can use
JavaServer Faces technology tags in a web page to link to server-side
objects without writing any scripts.

Another important goal of JavaServer Faces technology is to leverage
familiar component and web-tier concepts without limiting you to a
particular scripting technology or markup language. JavaServer Faces
technology APIs are layered directly on top of the Servlet API, as shown
in link:#GJEPW[Figure 7-2].

[[GJEPW]]

.*Figure 7-2 Java Web Application Technologies*
image:img/javaeett_dt_015.png[
"Diagram of web application technologies. JavaServer Pages, the JSP
Standard Tag Library, and JavaServer Faces rest on Java Servlet
technology."]

This layering of APIs enables several important application use cases,
such as using different presentation technologies, creating your own
custom components directly from the component classes, and generating
output for various client devices.

Facelets technology, available as part of JavaServer Faces technology,
is the preferred presentation technology for building JavaServer Faces
technology–based web applications. For more information on Facelets
technology features, see link:jsf-facelets.html#GIEPX[Chapter 8,
"Introduction to Facelets"].

Facelets technology offers several advantages.

* Code can be reused and extended for components through the templating
and composite component features.
* You can use annotations to automatically register the managed bean as
a resource available for JavaServer Faces applications. In addition,
implicit navigation rules allow developers to quickly configure page
navigation (see link:jsf-intro006.html#BNAQL[Navigation Model] for
details). These features reduce the manual configuration process for
applications.
* Most important, JavaServer Faces technology provides a rich
architecture for managing component state, processing component data,
validating user input, and handling events.


