# File lib/openshift-origin-controller/app/models/application.rb, line 564
  def start(dependency=nil, stop_on_failure=true)
    reply = ResultIO.new
    self.class.notify_observers(:before_start, {:application => self, :reply => reply, :dependency => dependency})
    self.start_order.each do |comp_inst_name|
      comp_inst = self.comp_instance_map[comp_inst_name]
      next if !dependency.nil? and (comp_inst.parent_cart_name != dependency)
      next if comp_inst.parent_cart_name == self.name

      begin
        group_inst = self.group_instance_map[comp_inst.group_instance_name]
        run_on_gears(group_inst.gears, reply) do |gear, r|
          r.append gear.start(comp_inst)
        end
      rescue Exception => e
        gear_exception = e.message[:exception]
        self.stop(dependency,false,false) if stop_on_failure
        raise gear_exception
      end
    end
    self.class.notify_observers(:after_start, {:application => self, :reply => reply, :dependency => dependency})
    reply
  end