dip_example_3.rb

class AmikoAdapter
  def initialize ; @amiko = Amiko.new(...) ; end
  def send_email
    @amiko.authenticate(...)
    @amiko.send_message(...)
  end
end
# Change the controller method to use the adapter:
def advertise_discount_for_movie
  moviegoers = Moviegoer.interested_in params[:movie_id]
  mailer = if Config.has_amiko? then AmikoAdapter else MailerMonkey end
  EmailList.new(mailer).send_email_to moviegoers
end