public class DogDriver {
    private class Animal {
        public String toString() {
            return "Animal";
        }
    }

    private class Dog extends Animal {
        public String toString() {
            return "Dog";
        }
    }

    private class HerdingDog extends Dog {
        public String toString() {
            return "herding_dog";
        }
    }

    private class WorkingDog extends Dog {
        public String toString() {
            return "working_dog";
        }
    }

    public void dogCaster(Dog aDog) {
        HerdingDog herdDog = (HerdingDog) aDog;
        System.out.println("Cast dog" + herdDog);
    }

    public void drive() {
        Object obInstance = new Object();
        Animal anInstance = new Animal();
        Dog dogInstance = new Dog();
        WorkingDog workInstance = new WorkingDog();
        System.out.println(anInstance + " " + dogInstance + " " + workInstance + " " + obInstance);
        Object obwork = workInstance;
        Animal andog = dogInstance;
        System.out.println(obwork + " " + andog);
        System.out.println(
                obwork.getClass().getName() + " " + andog.getClass().getName() + " " + obInstance.getClass().getName());
        dogCaster(workInstance);
    }

    public static void main(String[] args) {
        new DogDriver().drive();
    }

}