Java 8 method references - dereferenced only once?

I'm confused with method references. Consider the following script.

public class Main {

    static interface I {
        void m();
    }

    static class A implements I {
        @Override
        public void m() {
            System.out.println("A");
        }
    }

    static class B implements I {
        @Override
        public void m() {
            System.out.println("B");
        }
    }

    public static void main(String[] args) {
        A a = new A(); B b = new B();
        I i; Runnable r;
        i = a;
        r = i::m;
        r.run(); // prints "A"
        run(i); // also prints "A"
        i = b;
        r.run(); // prints "A" instead of "B"!
        run(i); // now prints "B"
        r = i::m;
        r.run(); // prints "B"
        run(i); // also prints "B"
    }

    public static void run(I i) {
        Runnable r = i::m; // polymorphic reference
        r.run();
    }
}

So it seems that:

• The compiler cannot inline method references because they are polymorphic. They are not resolved at compilation time, but at runtime.


• But i::m does not behave like i.m()...

So my question is:

Are method references using reflection? And why the hell only once?