JavaServer Faces
JavaServer Faces (JSF) is a user interface framework, or API, that eases the development of Java web applications.
WebSphere Application Server supports JavaServer Faces 2.2 at a runtime level. Use the JSF run time for the following functions:
- Construct a user interface from a set of reusable user interface components.
- Simplify migration of application data to and from the user interface.
- Help manage user interface state across server requests.
- Provide a simple model for wiring client-generated events to server-side application code.
- Support custom user interface components for build and reuse.
The Apache MyFaces implementation is included with WAS and provides the foundation of the code used for the JSF.
The version of the JSF run time that is included with the product resides in the normal runtime library location and is available to all web applications that use JSF APIs. Loading the JSF servlet works as if the run time was packaged with the web application. The bundled version includes enhancements for better integration with the built-in annotation scanning and other runtime components of WAS.
The specification-related classes javax.faces.* for JSF and the IBM modified version of the Apache MyFaces JSF Implementation is packaged in the run time.
Typically, web applications that use this API/Framework embed the JSF API and implementation JAR files within their web application archive (WAR) file. This is not required when these web applications are deployed and run within WAS. Only the removal of these JAR files along with any JSTL JAR files from the WAR file is required. However, because JavaServer Faces 2.2 is a part of the Java EE platform, a web application does not bundle a JavaServer Faces implementation when it runs on a web container that is Java EE technology compliant. If a JavaServer Faces implementation is bundled with a web application, it is ignored as the JavaServer Faces implementation provided by the platform always takes precedence.
The JSF run time for WAS does not support the use of a single class loader for the entire application because the FacesConfig initialization requires a single class loader for each JSF module during initialization. This support is not available when the application contains multiple web modules and one of those modules is a JSF module. Therefore, we must use multiple class loaders when the application contains multiple web modules and at least one JSF module.
For using different implementations of JSF, the WAS JSF engine determines if the SUN RI or Apache MyFaces is used from the application server run time. After the JSF engine determines the implementation used, the correct listener class is registered with the web container. We do not need to add the com.sun.faces.ConfigureListener or the org.apache.myfaces.StartupConfigureListener to the web.xml file.
If we use a third-party JSF implementation that is not included with the product, leave the configuration set to MyFaces, add the third-party listener to the web.xml file required; then, add the third-party implementation JAR files to the web module as an isolated shared library. Using an isolated shared library, the web application version of the JSF or JSTL classes load before the Application Server.
Related:
JavaServer Faces widget library (JWL) JavaServer Faces 2.2 feature functions Configure Portlet Bridge for JavaServer Faces Configure for JavaServer Faces 2.2 Configure for JavaServer Faces 2.2 Manage JavaServer Faces implementations Task overview: Develop and deploy web applications Developing web applications Configure JSF engine parameters JSF engine configuration parameters