python入门 类的继承和聚合(五)

继承

class Rocket:
    def __init__(self, name, distance):
        self.name = name
        self.distance = distance

    def launch(self):
        return "%s has reached %s" % (self.name, self.distance)

class MarsRover(Rocket): # inheriting from the base class
    def __init__(self, name, distance, maker):
        Rocket.__init__(self, name, distance)
        self.maker = maker

    def get_maker(self):
        return "%s Launched by %s" % (self.name, self.maker)

if __name__ == "__main__":
    x = Rocket("simple rocket", "till stratosphere")
    y = MarsRover("mars_rover", "till Mars", "ISRO")
    print(x.launch())
    print(y.launch())
    print(y.get_maker())

simple rocket has reached till stratosphere
mars_rover has reached till Mars
mars_rover Launched by ISRO

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聚合

class MarsRoverComp():
    def __init__(self, name, distance, maker):
        self.rocket = Rocket(name, distance) # instantiating the base
        self.maker = maker

    def launch(self):
        self.rocket.launch()

    def get_maker(self):
        return "%s Launched by %s" % (self.rocket.name, self.maker)

if __name__ == "__main__":
    z = MarsRover("mars_rover2", "till Mars", "ISRO")
    print(z.launch())
    print(z.get_maker())

mars_rover_comp has reached till Mars
mars_rover_comp Launched by ISRO