享元模式

class flower:
    def __init__(self):
        pass
    def buy(self):
        pass

class ShareFlower(flower):
    def __init__(self, color):
        self.color = color

    def buy(self):
        print(‘一朵 %s 的鲜花‘ % (self.color))

class Factory():
    def __init__(self):
        self.share = dict()

    def getFlower(self, color):
        if color not in self.share:
            print(‘not in‘)
            self.share[color] = ShareFlower(color)
        return self.share[color]

class UnShareFlower(flower):
    def __init__(self, color):
        self.color = color

    def buy(self):
        print(‘不共享一朵 %s 的鲜花‘ % (self.color))

flower = Factory()
blue_flower = flower.getFlower(‘blue‘)
red_flower = flower.getFlower(‘red‘)
red_flower1 = flower.getFlower(‘red‘)
red_flower2 = flower.getFlower(‘red‘)
black_flower = UnShareFlower(‘blak‘)
blue_flower.buy()
red_flower.buy()
red_flower1.buy()
red_flower2.buy()
black_flower.buy()