Question

i have to use the factory pattern with singleton.
My Factory Class creates two different objects depending on an enum type.

what is the best way to return the right object.

solution 1: by an if-else decision in the factory:

if(enumType == "objectA") return new objectA()

solution 2: the enum class has a return function:

enum ObjectType{ ObjectA{ .. return new ObjectA()..}}

thx, mike

Answer 1

Write a function on the enum. That way you’re not going to forget to add a clause to your factory method when you add a new enum.

As a rule, I’d favour polymorphism and method implementation over sequences of if/else if etc. for virtually any solution. It’s much less error prone, and issues will be caught at compile time, not run time.