Instantiating interfaces in Java

Question

I have this interface:

public interface Animal {
    public void Eat(String name);
}

And this code here implements the interface:

public class Dog implements Animal {
    public void Eat(String food_name) {
        System.out.printf(food_name);
    }

    public static void main(String args[]) {
        Animal baby2 = new Dog(); //HERE!!!!!!!!!!!!!!!!!!!!!!
        baby2.Eat("Meat");
    }
}

My question is, why does the code work? An interface cannot be instantiated. Yet in this case, interface was instantiated (marked with the comment "HERE!!!!!!!!!!!!!").

What is happening here?

question from:https://stackoverflow.com/questions/16750772/instantiating-interfaces-in-java

Answer 1

No it is not - you are instantiating a Dog, but since a Dog is an Animal, you can declare the variable to be an Animal. If you try to instantiate the interface Animal it would be:

Animal baby2 = new Animal();

Try that, and watch the compiler scream in horror :)