Inheritance Example

vehicles_part_1.py

__author__ = 'David Gotz, gotz@unc.edu, Onyen = gotz'


# Define the superclass Vehicle
class Vehicle:
    # Define the initialization method
    def __init__(self, driver):
        self.driver = driver
        self.passengers = None

    # Load a list of passengers into the vehicle
    def load(self, passengers):
        self.passengers = passengers

    # Unload the list of passengers.  Returns None if the vehicle is empty.
    def unload(self):
        passengers = self.passengers
        self.passengers = None
        return passengers


# GroundVehicle: a subclass of Vehicle for ground transportation vehicles
class GroundVehicle(Vehicle):
    # The initialization method
    def __init__(self, driver):
        # Call the superclass init
        Vehicle.__init__(self, driver)

    # Define a drive method
    def drive(self):
        print(self.driver + ": ", end="")
        for i in range(3):
            print("Vroom...", end="")
        print(self.passengers)


# AirVehicle: a subclass of Vehicle for air transportation vehicles
class AirVehicle(Vehicle):
    # The initialization method
    def __init__(self, driver):
        # Call the superclass init
        Vehicle.__init__(self, driver)

    # Define a fly method
    def fly(self):
        print(self.driver + ": ", end="")
        for i in range(3):
            print("Shhhh...", end="")
        print(self.passengers)


# A main function to coordinate the program
def main():
    # Vacation time! We will need to drive to the airport, fly to our destination airport, then drive to the hotel.
    # That means two taxis and a plane
    rdu_taxi = GroundVehicle("Alice")
    big_airplane = AirVehicle("Jane")
    hawaii_taxi = GroundVehicle("Bob")

    # Now let's go!  We will use:
    # 1. The same load method for all three vehicles
    # 2. Drive for cars.   Fly for planes.  These extend the base class Vehicle.
    passengers = ["Anne", "David", "Sarah", "Issac", "Adina"]
    rdu_taxi.load(passengers)
    rdu_taxi.drive()

    big_airplane.load(rdu_taxi.unload())
    big_airplane.fly()

    hawaii_taxi.load(big_airplane.unload())
    hawaii_taxi.drive()


# Start the program.
main()