JRuby Toolkit Robot example - How take a screenshot of your desktop

require 'java'

include_class 'java.awt.Dimension'
include_class 'java.awt.Rectangle'
include_class 'java.awt.Robot'
include_class 'java.awt.Toolkit'
include_class 'java.awt.event.InputEvent'
include_class 'java.awt.image.BufferedImage'
include_class 'javax.imageio.ImageIO'

toolkit = Toolkit::getDefaultToolkit()
screen_size = toolkit.getScreenSize()
rect = Rectangle.new(screen_size)
robot = Robot.new
image = robot.createScreenCapture(rect)
f = java::io::File.new('test.png')
ImageIO::write(image, "png", f)

http://www.devdaily.com/blog/post/ruby/jruby-code-that-takes-screenshot-of-your-desktop-saves-it-as-fi