Приклад фабричного методу мовою програмування Python
"""
Define an interface for creating an object, but let subclasses decide
which class to instantiate. Factory Method lets a class defer
instantiation to subclasses.
"""
import abc
class Creator(metaclass=abc.ABCMeta):
"""
Declare the factory method, which returns an object of type Product.
Creator may also define a default implementation of the factory
method that returns a default ConcreteProduct object.
Call the factory method to create a Product object.
"""
def __init__(self):
self.product = self._factory_method()
@abc.abstractmethod
def _factory_method(self):
pass
def some_operation(self):
self.product.interface()
class ConcreteCreator1(Creator):
"""
Override the factory method to return an instance of a
ConcreteProduct1.
"""
def _factory_method(self):
return ConcreteProduct1()
class ConcreteCreator2(Creator):
"""
Override the factory method to return an instance of a
ConcreteProduct2.
"""
def _factory_method(self):
return ConcreteProduct2()
class Product(metaclass=abc.ABCMeta):
"""
Define the interface of objects the factory method creates.
"""
@abc.abstractmethod
def interface(self):
pass
class ConcreteProduct1(Product):
"""
Implement the Product interface.
"""
def interface(self):
pass
class ConcreteProduct2(Product):
"""
Implement the Product interface.
"""
def interface(self):
pass
def main():
concrete_creator = ConcreteCreator1()
concrete_creator.product.interface()
concrete_creator.some_operation()
if __name__ == "__main__":
main()
