Yet another way to keep Java classes in Ruby, using OpenStruct;
require 'rubygems'
require 'rjb'
require 'ostruct'
Rjb::load
Java = OpenStruct.new(Hash[*%w{
java.io.File
}.map{|v| [v.split('.')[-1], Rjb::import(v)]}.flatten])
p Java.File.new('a.txt').toURI.toString