log4p

Yesterday I visited Proficts' Java Summercamp called "Rails en Grails en Java: Nieuwe talen op de JVM". Which in essence should have been a small seminar
on the topic of new languages on the JVM. In reality Charles Nutter presented JRuby, and its' current state and Graeme Rocher did a presentation on Groovy and Grails.

Both presentations resembled previous presentations (Finalist JRuby evening, Javapolis) I visited closely. Difference being that there was a bit more time to get into a tiny bit of detail.

First, let me walk you through the program:

13:00 Walter van Berkel (introduction)

Introduction of the organizing company. A "please come and work for us" presentation

13:30 Charles Nutter (JRuby)

Charles starts of the with the obligatory "who's got any experience with Ruby?".
Most people in the audience have nog hands-on experience with Ruby.

So, Charles starts of with explaining the basics of Ruby. Types, inheritance, closures, modules... a bit
dull if you do know a bit about Ruby.

On to the demo's

Demo: JFrame from JRuby using Netbeans 6

If you've seen Ruby calling into Swing before it's getting less impressive, people in the audience where getting interested

Demo: Interactive Java from jIrb

Reminded me of the fact that it is cool that JRuby can use JVM thread (Thread.new), which is actually quite nice.

Demo: 'Profligacy'

Another Swing demo, the LEL expressions used to define the interface where quite nice

Demo: Cheri builder framework

Another Swing demo; yes it can be done...

Demo: Rails on JRuby

90% of the audience was supposedly involved in webdevelopement. A Rails demo should have won them over. Charles didn't really manage to do this; he only did a really basic 2005 style scaffolding demo... bummer; but then again he really isn't a Rails guy... he's a JRuby guy.

Het demoed the use of the Rome RSS liberary to create an RSS feed using JRuby.
The deployement related part of the presentation managed to grab my attention though.
I knew of GoldSpike and that it is possible to create WAR files from Rails applications, but still cool.
I hadn't seen the GlassFish V3 preview Gem, which instantly runs your rails app on GlashFish. Really cool!

Demo: ActiveHibernate

I browsed through the ActiveHibernate examples just last week and decided that it is far to immature to call it a framework yet.
It managed to crash-and-burn horrible during the presentation; proving my point. Might be something some day... but not just yet.

16:00 Graeme Rocher (Grails - Next generation apps. Done quick.)

Graemes' presentation was structured quite similar to the presentation Charles gave. An introduction to the Groovy programming language, and on to the demos!

Demo: Scaffolding

Due to the pleasant look of models in GORM, and the fact that Grails' scaffolding automatically generated widgets for associations this demo was a bit
more up to date. Also the tag part, which triggered my interest in Grails at Javapolis managed to rouse people a bit.

Demo: Rendering / Builders

Graeme started of with using the XML builder for converting the object graph to XML, nice! Af this he demoed the 'render as' methods of Grails for rendering object graphs as XML and JSON. Cool! I'll write a post on this in the near future.
Back to GORM: the criteria builder:

PLAIN TEXT

GROOVY:

1. Book.withCriteria{
2.   like(title, "bla")
3. }

Cool as well!

Demo: Grails and WebFlow

Since Grails is based on Spring MVC the embracing of WebFlow in the new 0.6 release was to be expected. WebFlow is a conversational state engine.
The code looked, eh.. groovy... to bad the demo didn't run.

Conclusion
After the presentations I (and, as I understood from organizer Danny) hoped to get into a little debate on the use of scripting languages on top of the JVM. Not all Java developers came to the point where they bother about scripting languages just yet; the audience was actually more interested in asking detail questions about Rails and Grails. "Yes, Grails might have support for migrations after 1.0 has been released", "Rails can be as secure as you make it". This really made Grails stand out much better then the conventional Rails, but mostly due to the fact the Charles came in to talk about JRuby and Rails was just one of the demo's.

All in all, I had a splendid afternoon... but many Java developers still have a long, long way to go when talking about scripting languages!