You’ve created a fully functional Dog
class. Congratulations!
One of the object-oriented programming concepts that allows us to reuse and maintain code more efficiently is called inheritance. It is used to share or inherit behavior from another class. Let’s look at an example:
class Car extends Vehicle { int modelYear; public Car(int year) { modelYear = year; } //Other methods omitted for brevity... public static void main(String[] args){ Car myFastCar = new Car(2007) myFastCar.checkBatteryStatus(); } }
class Vehicle { public void checkBatteryStatus() { System.out.println("The battery is fully charged and ready to go!"); } }
In the example above, the extends
keyword is used to indicate that the Car
class inherits the behavior defined in the Vehicle
class. This makes sense, since a car is a type of vehicle.
Within the main
method of Car
, we call the checkBatteryStatus
method on myFastCar
. Since Car
inherits from Vehicle
, we can use methods defined in Vehicle
on Car
objects.
Instructions
Note that there are now two files in the code editor. Within the Dog
class, use the extends
keyword to inherit from the Animal
class.
Within the main
method of the Dog
class, call the checkStatus
method on the spike
object.