Elements In JSF

The JSF technology has its own set of elements, which together make this framework. The Core features of JSF are provided by these elements.  These Components are

• UI Component
• Renderer
• Validator
• Backing Beans
• Converter
• Events and Listeners
• Message
• Navigation

Describing UI Components:

           UI Component are the basic reusable components, such as labels, text boxes, and list boxes, used for developing user interface. We can define UI component as stateful objects maintained on the server side. the server communicates with the clients through these UI components. The components are simple JavaBeans Containing properties, methods, and events. The JSF UI components are also called Web application user interface components.

Describing the Renderer: 

          Most Web applications usually send a response to the web browser in the HTML format. Other client devices such as mobile phones or Personal Digital Assitants(PDAs) don't provide HTML browsers. some of the formats supported by these handled devices are WML and XHTML Basic. there, web applications need to respond in anther markup language. Since handheld technology is growing very fast, it is a good question to ask how existing applications can be supported by new devices.

      

         A renderer is a type of class that is responsible for encoding and decoding components

   1)Direct Rendering Model: The rendering logic is directly encapsulated into the UI component. therefore, there is no clear separation of functionality and presentation. This technique is used when we are sure that the component is being created for a particular client. as a result, the UI component is implemented in a single class. However, the reusability of the UI component is poor.

   2) In direct/ Delegated Rendering Model: This model uses a separate renderer for seperate UI component. Here this renderer, represented by the render class, does the work encoding and decoding. we can simply replace the set of renderer classes to display the output in a format compatible with some different  client