Select the correct answerWhat is the output of the following Java program?public class Vehicle { public void move() { System.out.println("The vehicle moves"); }}public class Car extends Vehicle { public void move() { System.out.println("The car moves"); }}public class Main { public static void main(String[] args) { Vehicle vehicle = new Car(); vehicle.move(); }}Options"The car moves""The vehicle moves"The code does not compileNone of these
Question
Select the correct answerWhat is the output of the following Java program?public class Vehicle { public void move() { System.out.println("The vehicle moves"); }}public class Car extends Vehicle { public void move() { System.out.println("The car moves"); }}public class Main { public static void main(String[] args) { Vehicle vehicle = new Car(); vehicle.move(); }}Options"The car moves""The vehicle moves"The code does not compileNone of these
Solution
The correct answer is "The car moves".
Here's the step-by-step explanation:
-
The
Vehicleclass has a method calledmove()that prints out "The vehicle moves". -
The
Carclass extendsVehicle, meaning it inherits all of its methods. However, it also has its ownmove()method that prints out "The car moves". This is an example of method overriding in Java. -
In the
mainmethod, aVehicleobject is created but it's actually aCar(Vehicle vehicle = new Car();). This is known as upcasting in Java. -
When
vehicle.move();is called, Java looks at the actual object thatvehiclerefers to, which is aCar, not aVehicle. Therefore, themove()method ofCaris called, not the one ofVehicle. -
So, "The car moves" is printed out.
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