So, in that case, is Johan Ander's son?Yes, that's how it works. Unless your name has 3 words/names in it and not just 2.
For example, I was named Sveinn Dagur, and my father's first name is Rafn. And thus I was named Sveinn Dagur Rafnsson.
I will admit that it is a fairly complex system that we use here, but that just makes us more special.