Before we even think about sending data to the server, we must first write a function that will be able to receive information. This function will be used to catch the data that is returned by the server.

The XMLHttpRequest object has a special property called onreadystatechange. onreadystatechange stores the function that will process the response from the server. The following code defines an empty function and sets the onreadystatechange property at the same time!

There is a lot of AJAX chats popping out, the reason: it is very simple to automate communication between client (AJAX part) and with java, it is easy to distribute messages between clients in server-side. I will show you the implementation used in SMS chat’s.

There are several niceties that everyone includes such as enter key interception and refocusing on the chat entry field, for examples of either, just look at the source attached. The server side in Java is just as easy.

Since servlets are created once per application, you can use init method to instantiate a chat holding String or a Buffer (or any other self created object). Since this object will be automatically shared per any request to the servlet, you just add messages to it and post back to each requestor. Synchronization can be implemented as and if needed.

Have you ever seen or wished you could have live data on your website? Have you got data stored in a database that updates regularly? This tutorial will explain how you can achieve this effect using AJAX and PHP. This can be achieved in almost any server side scripting language, as long as you know how to make database queries in your desired langauge. I suggest that you know how to use the basic XMLHttpRequest object.

Late last year Drew McLellan posted a great article on 24ways.org called Edit-in-Place with Ajax. Using Flick as an example and Prototype to do the heavy lifting he showed how to edit text inline. Like many other people I’ve been fascinated by this approach to altering text. After playing with Drew’s example off and on I finally sat down and decided to generalize it a bit more to make it easier to use

The presentation on Ajax Unplugged presented at ETech by Kevin Henrikson of Zimbra can be found here. This session covered various techniques in offline AJAX.

Zimbra Desktop is the next generation leap forward for Web 2.0 applications- now you can have Zimbra's Ajax-based collaboration experience online and offline. That means when you are out of the office without a connection (say, in a plane, train, or automobile), you can keep working without missing a beat. Write email, add new appointments, edit documents and when you re-connect changes will be automatically synced to the Zimbra Server.