Template Method Design Pattern in Python
"""
Define the skeleton of an algorithm in an operation, deferring some
steps to subclasses. Template Method lets subclasses redefine certain
steps of an algorithm without changing the algorithm's structure.
"""
import abc
class AbstractClass(metaclass=abc.ABCMeta):
"""
Define abstract primitive operations that concrete subclasses define
to implement steps of an algorithm.
Implement a template method defining the skeleton of an algorithm.
The template method calls primitive operations as well as operations
defined in AbstractClass or those of other objects.
"""
def template_method(self):
self._primitive_operation_1()
self._primitive_operation_2()
@abc.abstractmethod
def _primitive_operation_1(self):
pass
@abc.abstractmethod
def _primitive_operation_2(self):
pass
class ConcreteClass(AbstractClass):
"""
Implement the primitive operations to carry out
subclass-specificsteps of the algorithm.
"""
def _primitive_operation_1(self):
pass
def _primitive_operation_2(self):
pass
def main():
concrete_class = ConcreteClass()
concrete_class.template_method()
if __name__ == "__main__":
main()