adapter pattern

class Record
  def add_record
    raise 'Abastract method'
  end
end

class Event < Record
  def add_record
    puts '增加一条日志'
  end
end

class OrderEvent < Record
  attr_accessor :event

  def initialize
    @event = Event.new
  end

  def add_record
    puts '给订单'
    @event.add_record
  end
end

OrderEvent.new.add_record