Rails/Java Integration and Hosting

At the moment I'm a sub-contractor, doing mostly .NET work, with some Rails websites on the side just for fun. I'm considering applying for a position at a software company that will be pretty Java intensive, and I don't have much Java experience (a grand total of one significant project I did a year ago just for fun). I know a developer at the company, and he recommended I work up my java skills before applying. I love developing software, so I definitely want to do this, but the biggest issue is finding something interesting to work on. My current idea is to build a fractal-music generating web app based on an algorithm I developed back in college and originally implemented in a desktop .NET app. I'd like to use java for a good portion of it, but I'd rather not learn a new web app framework. I really, really like Rails. So, if possible, most of the web app will be in Rails, but all the midi manipulation will be done in Java. I've got a few questions that I'm hoping someone on here can help me with:

1. Is there a simple way to call a Java app/function/whatever from Rails? 2. The Rails hosts I've used before now (Rails Playground and A2 Hosting) don't provide support for Java. Anyone have any recommendations for a good hosts that supports both Rails and Java? 3. Alternately, I would consider using Java for the whole project if there is a Rails-like framework in Java that would allow me to re-use a lot of my rails experience and getup to speed without too much difficulty. I've been hearing about rails features being ported over to PHP, ASP.NET, etc...is there a good rails-like Java framework to use?

Thanks, Myron

At the moment I'm a sub-contractor, doing mostly .NET work, with some Rails websites on the side just for fun. I'm considering applying for a position at a software company that will be pretty Java intensive, and I don't have much Java experience (a grand total of one significant project I did a year ago just for fun). I know a developer at the company, and he recommended I work up my java skills before applying. I love developing software, so I definitely want to do this, but the biggest issue is finding something interesting to work on. My current idea is to build a fractal-music generating web app based on an algorithm I developed back in college and originally implemented in a desktop .NET app. I'd like to use java for a good portion of it, but I'd rather not learn a new web app framework. I really, really like Rails. So, if possible, most of the web app will be in Rails, but all the midi manipulation will be done in Java. I've got a few questions that I'm hoping someone on here can help me with:

1. Is there a simple way to call a Java app/function/whatever from Rails?   

Yes, there is: JRuby is your answer, I write a ruby app that runs inside JRuby, it works wery well (but for now I don't call any Java class method...).

JRuby is ruby interpreter written in Java and u can use ruby classes from Java and vice versa.

Now with 1.1 versione (1.1RC2 at this moment) the interpreter can compile ruby class (ahead of time and just in time), very cool !!!

If you want to run ruby apps inside GlassFish V3 app server give a try to glassfish gem ( http://rubyforge.org/frs/download.php/32339/glassfish-0.1.1-universal-java-1.5.gem )

2. The Rails hosts I've used before now (Rails Playground and A2 Hosting) don't provide support for Java. Anyone have any recommendations for a good hosts that supports both Rails and Java?   

Sorry, I don't know...

3. Alternately, I would consider using Java for the whole project if there is a Rails-like framework in Java that would allow me to re-use a lot of my rails experience and getup to speed without too much difficulty. I've been hearing about rails features being ported over to PHP, ASP.NET, etc...is there a good rails-like Java framework to use?   

The only other project I know is Grails (Groovy based) but if you have some Ruby/Rails experience the best choice is JRuby... (supported very well by NetBeans IDE, my best IDE friend since 2001...)

Have a nice day...