Is this interface being instantiated? (Java 8)

Question

As far as I know, interfaces cannot be instantiated directly. However, whenever I compile the following code:

interface A {};

public class Test {
   public static void main(String[] args){
       A a = new A() {};
       system.out.println(a);

it outputs the toString() of an object of class Test:

Test$16d06d69c

And when I change

A a = new A() {};

to

A a = new A();

it doesn't compile. Why is this happening? Is the interface being instantiated, or is something else happening behind the scenes?

Answer 1

You are defining a new anonymous inline class that implements interface A with the statement:

A a = new A() {};

And in the same statement you are constructing a new instance of your new anonymous class definition.

So no you are not instantiating an interface.