What to use – interface or abstract class to implement Factory pattern?

Both interfaces and abstract classes can be used to implement the Factory Pattern. The choice between them depends on the specific requirements of your application and design preferences. In general, if you need a simple factory pattern with just one method to create objects, an interface might be a better choice. If you need a more complex factory pattern with additional methods or common implementation details, an abstract class might be a better choice.

Here are some considerations:

1. Interfaces:
   • Use interfaces when you want to provide a contract for creating objects without specifying their implementation details.
   • Interfaces are useful when you have multiple unrelated classes that need to be created by the factory.
   • Interfaces are more flexible because a class can implement multiple interfaces.
2. Abstract Classes:
   • Use abstract classes when you want to provide a partial implementation for the factory method.
   • Abstract classes are useful when you have a common implementation for some of the methods in the factory, but you want subclasses to implement the factory method.
   • Abstract classes can provide a default implementation for the factory method, which can be overridden by subclasses.