Going to JRubyConf inspired me enough to expand my knowledge of JRuby. This is a quick guide for anyone looking to see what can be done with JRuby and Sinatra.
Of course the first step is to install the Java JDK. Download, install and then set it up in your path. I'm using JDK 6 update 21 on Linux for this post in case it matters.
There are a couple ways to install JRuby after you have Java installed. The hard way is to download JRuby and install it by hand. The easy way is to use Ruby Version Manager to install it. Using RVM will let you switch between Ruby versions as well as giving you a simple command to install JRuby:
rvm install jruby
rvm use jruby
I've been playing around with the Ruby/Rails cloud provider Heroku a little bit lately just to try it out. It is somewhat like Google App Engine or Microsoft Azure in the way it works since you bundle your application and push it out to the Heroku cloud for deployment. It is very easy to get things going but I ran into a few interesting items that I figured I would share.