/**
  * A convenience function for dumping all the elements of the received list into this class'
  * instance.
  *
  * @param items The list to union.
  */
 public void addResources(ResourceList<T> items) {
   resources.addAll(items.getResourceQueue());
 }
  /**
   * Will completely cancel the order by removing any FoodItems being cooked or prepared, remove the
   * Order from the waiting to be delivered queue, removing the order from the Truck that is
   * performing the driving to the Location or delivering to the customer.
   *
   * @param order The order to be canceled.
   */
  public void cancelOrder(Order order) {

    // To avoid a LOT of potential work, we are going to see where
    // the Order is and try to cancel only the parts we need to.
    ResourceList<Order> deliverables = over_seer.getNewOrders();
    if (deliverables.containsResource(order)) {

      // no point in doing all that looping and checks if the order
      // already cooked everything and is just waiting to be
      // delivered.
      if (!order.isAvailable()) {

        // first, check if any Chefs are preparing any FoodItems
        // contained in this Order.
        List<Chef> chefs = over_seer.getChefsWorkingOnOrder(order);
        for (Chef chef : chefs) {
          chef.cancelPreparation();
        }

        // Next, check for any Ovens that may be cooking CookedItems
        // contained in this Order.
        List<Oven> ovens = over_seer.getOvensWorkingOnOrder(order);
        for (Oven oven : ovens) {
          oven.stopCookingFoodFromOrder(order);
        }
      }

      // Remove all FoodItems from the food waiting to be processed
      ResourceList<FoodItem> foods = over_seer.getFood();
      for (FoodItem food : order.getFoodItems().getResourceQueue()) {
        foods.removeResource(food);
      }

      deliverables.removeResource(order);
    } else {

      // Since the order wasn't waiting to be delivered we need to find
      // the truck that is delivering it and cancel the order.
      Truck delivering_truck = over_seer.getOutboundTruckDeliveringOrder(order);
      if (delivering_truck != null) {
        delivering_truck.removeOrder(order);

        // Send the truck back to the pizza shop if he no longer has
        // orders to deliver.
        if (delivering_truck.getNumOrders() == 0) {
          int return_time =
              delivering_truck.getETAToLocation()
                  - (delivering_truck.getAvailTime() - time.getCurrentTime());
          delivering_truck.setETAToLocation(return_time);
          over_seer.getOutboundTrucks().removeResource(delivering_truck);
          over_seer.getInboundTrucks().addResource(delivering_truck);
        }
      } else {

        // Alright, now we need to check if it is already at the
        // Location but has *yet* to deliver the order.
        delivering_truck = over_seer.getTruckDeliveringOrderToCustomer(order);
        if (delivering_truck != null) {
          delivering_truck.removeOrder(order);

          // Send the truck back to the shop if it no longer needs
          // to give any customers their orders.
          if (delivering_truck.getNumOrders() == 0) {
            over_seer.getDeliveryTrucks().removeResource(delivering_truck);
            delivering_truck.setETAToLocation(delivering_truck.getETAToLocation());
            over_seer.getInboundTrucks().addResource(delivering_truck);
          }
        }
      }
    }
    order.cancelOrder();
  }