h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

The people I know who have had to implement anything in Java are always citing the problem of the lack of compatibility in the various JVMs. What's your experience of this?

Well, to answer that could take some time

In the early days of Java (1995, Java 1.0), the AWT (the graphics subsystem) was simplistic in the extreme and was written very badly. Consequently, most people did evil hacking to get round this nad produced incompatible code - Corel are the most famous, they did all sorts of unspeakable things to make their Java offfice suite run. Of course, if you didn't use the AWT there was no real problem.

Then in 1996/7, Java 1.1 was introduced with a new AWT which started to eliminate some of the problems. The introduction of JFC (Swing) has meant that now, user interface programming in Java runs into very few problems. Indeed, the manager of IBM's Sna Francisco project was telling me a month or so back that thet were experiencing precious little cross-platform interoperability these days.

So today, it's a historic throwback or an urban myth. And in your case, I would strongly suggest use of Java as a server technology, where the 'platform issue' doesn't arise because (a) you're not writing client GUI code, and (b) you're in control of the platforms.

The other Urban Myth is performance. Today, Java performance on the server is very good, and I'm aware of some very significant server projects using server-side Java. Indeed, I'm aware of many companies who are betting the business on it!

Assuming you're using Windows code running via CGI, I suspect you could get big improvements by using Servlets. I'd be happy to find you an expert to talk to if you wish, just e-mail me.

Well, don't be misled by the .cgis you see in the site. We're definitely not running each script as a CGI process. That would be insane. We're actually running Perl, using precompiled scripts. This is, I think, the source of any instability you might see in the servers. (See my journal entry entitled 800 megabytes).

And if we were to rewrite this, I think we'd probably go down a different route than Java, simply because I wouldn't want to switch to a language with which I'm less than familiar.

But thanks for the offer.

Fairy 'nuff. Hope you get to the bottom of your allocation problems soon! When the idle moment comes round (I don't know who's got it at the moment, I've been waiting for months for 'em to pass it on), do tinker with a little baby servlet though, they could certainly become your friends! If you want a free copy of VisualAge for Java, just drop me a note...

Well I for one have had much less trouble runing java code betwen MS and sun vms and from versions to version 1.0 -> 1.1 -> 1.2 and platforms W95/NT/Linux than I've had moving Microsoft code to the next version of the MS studio (VB, C++). I guess you just have to keep things in perspective.

-Peace

I absolutely agree. I often hear folk (usually people who don't use Java, I have to say) complaining about Java things as if the alternative was perfection. Especially now we have really fast & stable JVMs like the IBM ones and high levels of compatibility because of the Sun test suites for JVMs and widespread adoption because of Oracle, Weblogic, BEA etc I routinely find people saying that Java provides the best server solution yet. Note that they don't say it's perfect; just that, despite not being able to get heaven, they'd still rather be with Java than still living in hell...