Is it OK for a factory method to return null?
c#, design-patterns, factory-method, oop
Solution
I think it's potentially reasonable for a factory method to return null in some situations, but not if it's a method called `CreateCommand`. If it were `GetCommand` or `FetchCommand`, that might be okay... but a `Create` method should throw an exception on failure, I would suggest.
Whether you really want it to return `null` in this situation depends on the bigger picture, of course. (Is there a reasonable null object implementation you could return instead, for example?)
Problem
I'm wondering about best practice here. Is it good practice for a factory method to return null if it can't create anything? Here's an example: ``` ICommand command = CommandFactory.CreateCommand(args); if (command != null) command.Execute(); else // do something else if there is no command ``` An alternative would be to return a `NullCommand` or something, I guess, but what is best practice?