Passing arguments to a specific subclass, through a factory method

Question

Let's say I have an abstract class Drink, and a factory method which chooses the type of Drink (Wine, Beer, etc.) to create at runtime.

Each Drink needs some arguments to properly initialize itself. Some of these are common to all Drinks; for example, they might all require a DrinkConfig argument.

But each Drink may have its own unique requirements too. Maybe Wine needs a Sommelier helper object to initialize itself. Beer doesn't need that, but it may need its own helper objects.

So what should I pass to the factory method? When I call it, I have all the helper objects available, so I could just pass all of them to the factory. But this could end up being a lot of arguments. Is there a better way to design this?

EDIT: Let's assume I can't just create the helper objects in the factory; they're only available from the caller.

Answer 1

I'd create different overload methods in your factory class.

public class DrinkFactory {

    public static Drink CreateBeer(DrinkConfig config, string hops) {
        return new Beer(config, hops);
    }

    public static Drink CreateWine(DrinkConfig config, string grapes, int temperature) {
        return new Wine(config, grapes, temperature);
    }
}

Edit:

If it's desired to to only have a single method in the Factory class an alternative implementation would be:

public enum DrinksEnum {
    Beer,
    Wine
}

public class DrinkFactory {

    public static Drink CreateDrink(DrinksEnum drinkType, DrinkConfig config) {
        switch(drinkType) {
            case DrinksEnum.Beer:
                return new Beer(config);
            case DrinksEnum.Wine:
                return new Wine(config);
            default:
                throw new ApplicationException("Drink type not recognised.");
        }
    }
}