adii1823
58 lines
1.2 KiB
Python
58 lines
1.2 KiB
Python
# oop/class_inheritance.py
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class Engine:
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def start(self):
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pass
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def stop(self):
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pass
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class ElectricEngine(Engine): # Is-A Engine
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pass
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class V8Engine(Engine): # Is-A Engine
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pass
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class Car:
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engine_cls = Engine
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def __init__(self):
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self.engine = self.engine_cls() # Has-A Engine
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def start(self):
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print(
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'Starting engine {0} for car {1}... Wroom, wroom!'
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.format(
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self.engine.__class__.__name__,
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self.__class__.__name__)
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)
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self.engine.start()
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def stop(self):
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self.engine.stop()
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class RaceCar(Car): # Is-A Car
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engine_cls = V8Engine
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class CityCar(Car): # Is-A Car
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engine_cls = ElectricEngine
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class F1Car(RaceCar): # Is-A RaceCar and also Is-A Car
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pass # engine_cls same as parent
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car = Car()
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racecar = RaceCar()
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citycar = CityCar()
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f1car = F1Car()
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cars = [car, racecar, citycar, f1car]
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for car in cars:
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car.start()
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"""
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$ python class_inheritance.py
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Starting engine Engine for car Car... Wroom, wroom!
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Starting engine V8Engine for car RaceCar... Wroom, wroom!
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Starting engine ElectricEngine for car CityCar... Wroom, wroom!
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Starting engine V8Engine for car F1Car... Wroom, wroom!
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"""
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