The <a4j:ajax> behavior allows Ajax capability to be added to a non-Ajax component. The non-Ajax component must implement the ClientBehaviorHolder interface for all the event attributes that support behavior rendering.

The <a4j:attachQueue> behavior is used together with a <a4j:queue> component to further customize queuing for particular components and behaviors. The <a4j:attachQueue> behavior can override the scope-wide queue settings for an individual component, or attach specific requests to a queue.

The <a4j:commandButton> component is similar to the JavaServer Faces (JSF) <h:commandButton> component, but additionally includes Ajax support.

The <a4j:commandLink> component is similar to the JavaServer Faces (JSF) <h:commandLink> component, except that it includes plugged-in Ajax behavior.

The <a4j:jsFunction> component performs Ajax requests directly from JavaScript code and retrieves server-side data. The server-side data is returned in JavaScript Object Notation (JSON) format prior to the execution of any JavaScript code defined using the "oncomplete" attribute.

The <a4j:log> component generates JavaScript that opens a debug window, logging application information such as requests, responses, and DOM changes.

The <a4j:mediaOutput> component is used for generating images, video, sounds, and other resources defined on the fly.

The <a4j:outputPanel> component is used to group together components in to update them as a whole, rather than having to specify the components individually.

@author asmirnov@exadel.com

The <a4j:param> behavior combines the functionality of the JavaServer Faces (JSF) components <f:param> and <f:actionListener>.

The <a4j:poll> component allows periodical sending of Ajax requests to the server. It is used for repeatedly updating a page at specific time intervals.

The <a4j:push> component performs real-time updates on the client side from events triggered at the server side. The events are pushed out to the client through the RichFaces messaging queue (which is bound to Java Messaging Service - JMS). When the <a4j:push> component is triggered by a server event, it can in turn cause Ajax updates and changes.

The <a4j:queue> component manages the JSF queue of Ajax requests. It provides additional options for a finer control of request processing.

The <a4j:region> component specifies a part of the JSF component tree to be processed on the server. The region causes all the a4j and rich Ajax controls to execute: decoding, validating, and updating the model. The region causes these components to execute even if not explicitly declared. As such, processing areas can more easily be marked using a declarative approach.

Regions can be nested, in which case only the parent region of the component initiating the request will be processed.

The non-visual <a4j:repeat> component is used to iterate through a data model. The component renders child content for every iteration according to the current object data.

The <a4j:status> component displays the status of current Ajax requests. The status can be either in progress, complete, or an error is shown after a failed request.