py abstract_factory_pattern.md

# coding: utf8
"""
抽象工厂: 解决复杂对象创建问题
"""


class Frog:
    def __init__(self, name):
        self.name = name

    def __str__(self):
        return self.name

    def interact_with(self, obstacle):
        """ 不同类型玩家遇到的障碍不同 """
        print('{} the Frog encounters {} and {}!'.format(
            self, obstacle, obstacle.action()))


class Bug:
    def __str__(self):
        return 'a bug'

    def action(self):
        return 'eats it'


class FrogWorld:
    def __init__(self, name):
        print(self)
        self.player_name = name

    def __str__(self):
        return '\n\n\t----Frog World -----'

    def make_character(self):
        return Frog(self.player_name)

    def make_obstacle(self):
        return Bug()


class Wizard:
    def __init__(self, name):
        self.name = name

    def __str__(self):
        return self.name

    def interact_with(self, obstacle):
        print('{} the Wizard battles against {} and {}!'.format(
            self, obstacle, obstacle.action()))


class Ork:
    def __str__(self):
        return 'an evil ork'

    def action(self):
        return 'kill it'


class WizardWorld:
    def __init__(self, name):
        print(self)
        self.player_name = name

    def __str__(self):
        return '\n\n\t------ Wizard World -------'

    def make_character(self):
        return Wizard(self.player_name)

    def make_obstacle(self):
        return Ork()


class GameEnvironment:
    """ 抽象工厂，根据不同的玩家类型创建不同的角色和障碍 (游戏环境)
    这里可以根据年龄判断，成年人返回『巫师』游戏，小孩返回『青蛙过河』游戏
    这里的形参 factory 就是抽象工厂"""

    def __init__(self, factory):
        self.hero = factory.make_character()
        self.obstacle = factory.make_obstacle()

    def play(self):
        self.hero.interact_with(self.obstacle)