Python的抽象工廠模式

import random


class PetShop:

 """寵物商店"""

 def __init__(self, animal_factory=None):

 """寵物工廠是我們的抽象工廠。我們可以隨意設(shè)置。""" 
 self.pet_factory = animal_factory

 def show_pet(self):

 """使用抽象工廠創(chuàng)建并顯示一個寵物"""

 pet = self.pet_factory.get_pet()
 print("我們有一個可愛的 {}".format(pet))
 print("它說 {}".format(pet.speak()))
 print("我們還有 {}".format(self.pet_factory.get_food()))


# 工廠生產(chǎn)的事物

class Dog:

 def speak(self):
 return "汪"

 def __str__(self):
 return "Dog"


class Cat:

 def speak(self):
 return "喵"

 def __str__(self):
 return "Cat"


# Factory classes

class DogFactory:

 def get_pet(self):
 return Dog()

 def get_food(self):
 return "狗食"


class CatFactory:

 def get_pet(self):
 return Cat()

 def get_food(self):
 return "貓糧"


# 隨機(jī)創(chuàng)建合適的工廠
def get_factory():
 """讓我們動起來！"""
 return random.choice([DogFactory, CatFactory])()


# 多個工廠顯示寵物
if __name__ == "__main__":
 for i in range(4):
 shop = PetShop(get_factory())
 shop.show_pet()
 print("=" * 20)