Practical RichFaces, Second Edition

CHAPTER 1 THE BASICS
This example looks very similar to the RichFaces 3 example. The obvious changes are the new
behavior (), the event is specified without the on-part and instead of reRender, the render
attribute is used. However, the core Ajax concepts are very similar. In addition to using
behavior, it’s also possible to send an Ajax request in a programmatic way, as follows:
Even though basic, Ajax is now part of the JSF 2 standard. We will cover more features later
in the book.
Before we tell you more about RichFaces, we must ask: why would you use JSF? Well, the shortest
answer is that (after a short learning curve) JSF simplifies development. The basic purpose of any
framework is to simplify development by hiding the tasks that are common to any application. JSF does
exactly that. You don’t have to worry anymore about how to get data from the request or how to define
navigation or convert values. JSF provides all this and more out of the box. If all the plumbing is covered
by the framework, that leaves you more time to work on the actual application. Finally, a JSF component
approach makes it the perfect technology to be used with Ajax.
An Overview of RichFaces
If you are wondering why we need RichFaces if there is now Ajax functionality in JSF 2, it’s because the
Ajax functionality in JSF 2 is very basic. You only get behavior. That’s not enough to build real
rich enterprise Ajax applications. That’s exactly why you need RichFaces, a rich framework for JSF. It
consists of the following parts:
• Rich and Ajax components divided into two tag libraries (a4j:, rich:)
• Skins
• Client-side and object validation extension for Bean Validation (JSR 303)
• CDK (Component Development Kit)
Besides these main parts, RichFaces extends the standard JSF 2 Ajax request queue, and adds
various rendering optimization attributes that we will cover in this book. A RichFaces application can
also be deployed in the cloud, to places such as GAE (Google Apps Engine), Amazon EC2, and
CloudBees, and OpenShift. RichFaces not only extends JSF, it makes JSF richer. In fact, you can’t use
RichFaces without JSF. You use RichFaces with either the Mojarra JSF (Oracle RI) implementation or the
MyFaces implementation. RichFaces simply provides ready-to-use Ajax components (and other
features) to enable building Ajax-based applications. Another way to look at it as extra JSF components
beyond what standard JSF provides. These components provide all the necessary JavaScript, so you
almost never have to work with JavaScript directly.