This year at JavaOne was the first time since 1999 that I actually got to attend a bunch of sessions, thanks to not having to man an OpenLogic booth.  Overall, it was quite good.  There were quite a few parallel tracks and always something interesting in at least one of them.

Perhaps unsurprising, but the major themes were:

• SOA
• AJAX
• Dueling component frameworks (JBI, SCA, OSGi)
• Scripting languages for the JVM (JRuby, Groovy, Scala)

SOA 

I expected to see SOA take off this year, but not quite to the extent I found at the show.  It seems that 2008 is truly the year that SOA goes from paper to reality.  There were a number of real users presenting case studies around their migration to SOA, performance implications, and lessons learned.  There was a separate sub-pavilion of vendors, both open source and proprietary, showing off their SOA-related businesses, tools, and services.  I think it's finally getting real.

AJAX

The growth of AJAX (aka Ajax) continues to surprise me.  The number of AJAX-related open source projects seems to be increasing at a faster and faster pace lately.  Along these lines, I saw sessions pitching Javascript for both client and server, sites that allow pseudo-technical users to create their own mashups visually, a number of widget libraries that sit on common toolkits such as Prototype and Script.aculo.us, and sessions on improving the user experience.  I also attended a few sessions on advanced web security that should make AJAX implementation a lot more interesting for the average developer. 

One related presentation recommended that developers turn their application into a platform so ordinary users can create their own content and even deploy mini-applications a la the Facebook Platform.  This clearly doesn't fit every application, but it certainly helps increase your Network Effect when it does.

Dueling Component Frameworks

In the "too many ways to do this" department, I saw sessions on JBI, SCA, and OSGi.  Yes, they're all about integration, but they each have their own niche.  JBI seems to be about creating business components that can be integrated across vendors, SCA seems more about integrating your own components within an application, and OSGi seems to be about integrating components from multiple vendors in your application.  If that isn't crystal clear, it's not you.

In the OSGi arena, SpringSource has recently announced their Application Platform which is built on OSGi.  This has rightly set off a firestorm of responses as it means the company is placing a big bet against the traditional application servers.  It could win big, lose big, or simply be ignored.  Only time will tell.

Scripting Languages for the JVM

I've spoken on Groovy for years and on JRuby for a while now, but this year at JavaOne they both had a much larger following than I expected.  Each of them has improved so much in the last 12 months that it's truly hard to imagine how they did it.  Their feature sets, stability, and performance have gone from "interesting – keep an eye on it" to "wow, this is the real deal".  We now have JRuby on Rails versus Groovy on Grails, both of which are fast and easy to use.  Just like Java with its incredible JVM, your JRuby/Rails and Groovy/Grails code will continue to get faster, more scalable, and use less memory over time without any code changes on your part.  I can't wait to see how far they'll go by next year!

Parting Thoughts 

One last comment on the show.  It seems to me that Sun is really starting to get serious about making itself known in the open source space lately.  Of course, there's the MySQL acquisition and OpenSolaris, but there's also the fact that they have an open source tool that competes with VMware (VirtualBox).  They're also going to release a site soon that provides open source software project hosting similar to SourceForge.net or java.net.  Their IDE, NetBeans, is now arguably the best platform for development Ruby on Rails apps (or at least JRuby on Rails apps).  They've released a GUI that makes it easy to visualize MySQL performance on OpenSolaris through DTrace (there's also a NetBeans plug-in for DTrace).  The list goes on.

I think they've realized that they've never really been able to capitalize on software, so why not open source it and gain some attention via the halo effect?  They seem to be doing a good job of that lately, but we'll have to give the MySQL move some time before making the final judgment.