Simplest possible JRuby+Java test

Bar.java

public class Bar {
  public static int baz() {
    return 1;
  }
}

bar_spec.rb

#!/usr/bin/env jruby

require 'java'
java_import 'Bar'
require "minitest/autorun"

describe Bar do
  describe "baz" do
    it "must return 1" do
      Bar.baz.must_equal 1
    end
  end
end