Is the main purpose of "Casting" to allow you to share methods and properties between child and parent classes?

// a superclass with a method
public class Bicycle {
    public void drive() {
        System.out.println("I am driving a fancy Bicycle");
    }
}
..........................................

// a subclass that inherits from superclass
public class MountainBike extends Bicycle {
}
..........................................

// your Test class where the sublass calls the superclass method
public class Test {
    public static void main(String[]arg) {
        MountainBike mnt1 = new MountainBike();
// the drive() method from the super class can be used by subclass  
               mnt1.drive();
    }
}

public class MountainBike{
    public void drive(MountainBike bike) {
        System.out.println("I am driving a fancy Mountainbike");
    }
}
...........................................
public class Test {
    public static void main(String[]arg) {
        Object obj = new Object();
        MountainBike mnt1 = new MountainBike();
        mnt1.drive((MountainBike) obj);
    }
}