In this interview, Dave Crane not only talks about Ajax but also about how Ajax can fit into the kind of applications and frameworks we are used to working with today. He also tells us why he feels Ajax has become so popular in such a short time and what lies in the future for Java based Ajax development.Dave is the author of "Ajax in Action" and has been working with Ajax technologies for several years.

IndicThreads >> Hi Dave. Congratulations on the publication of your book “Ajax In Action”. Could you tell us a little more about yourself and your involvement in Ajax?

Dave Crane >> Hi! Thanks, it's a real buzz to see the book out there, and getting such a good reception.

I've been working with the web for roughly ten years now, and watched JavaScript growing up. My main line of work has always been something else – Perl, Java, etc. - but JavaScript kept creeping into everything that I did. Five years ago, I found myself on a project developing set-top box systems using JavaScript, which gave me my first experience of maintaining a very large JS codebase. Since then, I tended to apply what-we-now-know-as-Ajax style approaches to my web app coding, using a variety of the old hidden iframe tricks and so on.

My second big experience with JavaScript was at SmartStream Technologies, working with a very smart team of J2EE developers on financial applications that were deployed to call centre-like setups in some of the tier-1 banks. Using the web browser to deliver the main application that a user would be pounding away on for eight hours a day was a pretty big challenge, and I have to say that we met it pretty well. Of course, there was a lot of Ajax going on in there.

"The Ajax technologies themselves aren't particularly new or sexy..."

Other than that, I'm just another computer fanatic who likes tinkering around with these pesky machines. I started writing code on a BBC Micro when I was fourteen, and currently use Linux, Windows and Mac OS X. I've contributed bits and pieces to various open source projects over the years, and like to code in Java, Python, Ruby and, of course, JavaScript!

IndicThreads >> As Ajax is such a new thing and only a handful are sure of what Ajax is all about, could you give us your thoughts on “What is Ajax”?

Dave Crane >> Well, it isn't a technology. At the risk of sounding a bit fluffy, I'd say it's a way of doing new things with old technologies. From the programmer's perspective, everything that we needed to do Ajax has been available for several years, but it's taken most of us this long to get it. A few brave souls like Brent Ashley, Eric Costello, and the people that I'm now working with at Historic Futures, have been pioneering this approach for some time, but it was never mainstream until recently.

"Ajax is a way of doing new things with old technologies..."

To the coder, Ajax is just a new way of using all the DHTML technologies, such as JavaScript, CSS and the DOM. Because you can get by longer without full-page refreshes, those technologies suddenly become more useful. To the architect and the business-person, it's more of a challenge, because it ousts some of the user flow control from the presentation tier, and requires a rethink of how the server-side works too.

"Adding asynchronous requests into the mix increases the reach of these technologies..."

To me, that's the most interesting thing about Ajax. As techies, we tend to get hung up on the Next Big Thing technology-wise (OK, i should speak for myself, I get hung up on these things), and yet with Ajax, the technologies themselves aren't particularly new or sexy. Rather, it's the realisation that new things can be done with the old technologies. Simply adding asynchronous requests into the mix increases the reach of these technologies to the 'sovereign' applications that users use as their main workhorse for several hours a day. We're seeing people like 37signals suddenly make sense of the ASP model that's been talked about for several years and never quite taken off until now. And once you get into the whole Web 2.0 thing of 'mash-ups' and published APIs, then the entire business model is changing further still.

IndicThreads >> In a very short time, Ajax has perhaps become the most popular acronym in software development. What do you think are the reasons? Did you see this coming?

Dave Crane >> No, I didn't see it coming, much as I'd like to nod my head sagely :-). I think the popularity of Ajax lies in the low barrier to entry. Writing an Ajax app needs nothing more than a text editor and a web browser, although a serious Ajax professional will probably want a whole array of debuggers, IDE's and DOM Inspectors up their sleeves too – I certainly do.

"The popularity of Ajax lies in the low barrier to entry..."

Web sites can adopt it incrementally, again, making the barrier to entry pretty low.

If you compare Ajax to, say, Java Web Start, then web start wins on sheer power and what you can do with it. But Ajax is good enough for most situations, and it's ready to run on most people's computers without installing any client software. Maybe the fact that it uses a scripting language has something to do with it too (I'm a big fan of scripting as much as possible, I got a great productivity boost personally out of jython, for example, when i first picked it up a few years ago.)

"I'm a big fan of scripting as much as possible..."