how to schedule a newScheduledThreadPool in jruby

newScheduledThreadPool_jruby.rb

require 'java'
java_import 'java.util.concurrent.Executors'
java_import 'java.util.concurrent.TimeUnit'

class SomeClass
  include java.lang.Runnable
  def run
    puts "imma lil jruby runner"
  end
end

class Scheduler
  def schedule
    puts "starting..."
    service = Executors.newScheduledThreadPool(1);
    service.scheduleAtFixedRate(SomeClass.new, 4, 2, TimeUnit::SECONDS);
    puts "i can haz service? #{service.class}"
    puts "done..."
  end
end
Scheduler.new.schedule

Depending on what's in your real SomeClass, you might want to schedule a shutdown:

Signal.trap("SIGINT") do # or whatever signals end your app
  scheduler.shutdown
  scheduler.await_termination(2,TimeUnit::SECONDS)
end

This will tell the schedule not to start any new threads, and the second call will wait 2 seconds for any threads that are running to shut down. You could also do shutdown_now to force an exit (but calling exit would likely do that, too :)

Thanks Dave! :-)