Factory method is a creational design pattern which solves the problem of creating product objects without specifying their concrete classes.
The Factory Method defines a method, which should be used for creating objects instead of using a direct constructor call (new operator). Subclasses can override this method to change the class of objects that will be created.
If you can’t figure out the difference between various factory patterns and concepts, then read our Factory Comparison.
Usage examples: The Factory Method pattern is widely used in Ruby code. It’s very useful when you need to provide a high level of flexibility for your code.
Identification: Factory methods can be recognized by creation methods that construct objects from concrete classes. While concrete classes are used during the object creation, the return type of the factory methods is usually declared as either an abstract class or an interface.
This example illustrates the structure of the Factory Method design pattern. It focuses on answering these questions:
What classes does it consist of?
What roles do these classes play?
In what way the elements of the pattern are related?