建造模式

和第一个抽象工厂模式有点像，继承共同的抽象类，统一出口，不过这里的出口是生产对象进程，抽象工厂模式是统一方法

class Building(object):
    def __init__(self):
        self.floor = None
        self.size = None

    def __repr__(self):
        return 'Floor: {0.floor} | Size: {0.size}'.format(self)
class Builder(object):

    def __init__(self):
        self.building = None

    def new_building(self):
        self.building = Building()

    def build_floor(self):
        raise NotImplementedError

    def build_size(self):
        raise NotImplementedError

class BuilderHouse(Builder):

    def build_floor(self):
        self.building.floor = 'One'

    def build_size(self):
        self.building.size = 'Big'

class BuilderFlat(Builder):

    def build_floor(self):
        self.building.floor = 'More than One'

    def build_size(self):
        self.building.size = 'Small'

def construct_building(builder):
    bulider.new_building()
    builder.build_floor()
    builder.build_size()
    return builder.building

# Client if __name__ == "__main__":     building = construct_building(BuilderHouse())     print(building)     building = construct_building(BuilderFlat())     print(building)