Overview

Overview

The essence of Ajax Push is the ability to trigger updates to the client from events or changes that occur on the server. This makes Ajax Push highly suitable for collaborative applications where one user does something that changes the current state of the application and other users are interested in seeing that change. There are many different ways to take advantage of Ajax Push to add collaborative features to your rich web application. From the developer's perspective, Ajax Push is exposed through the SessionRenderer API. This tutorial is designed to provide a simple and clear illustration of how to get started with the SessionRenderer API to add Ajax Push to your application.

The project we are going to build in this tutorial is a page that contains simple, adjustable counters. The counter values are displayed on the page and buttons are provided that can be used to increment or decrement the counter values. The finished project looks like this:

Figure 11 Easy Ajax Push Counter Project

The application consists of two counters. One is an application-scoped counter that can be adjusted and seen by all users. The second counter is session-scoped so changes to the value of this counter are restricted to the individual user. The goal is to use the SessionRenderer API so that any modifications to the application-scoped counter result in Ajax Push updates being sent to all application users.

All the source code for this tutorial is available in the ICEfaces bundle:
[install_dir]/samples/tutorial/easyajaxpush
 