Anonymous Inner Classes need to override their existing methods?

So I created an anonymous Inner Class via

    obj.addMouseListener(new MouseListener()

but because it gave me an error (it wanted me to implement at least 4 methods with names like mouseReleased, mouseClicked, etc. As I assumed the class didn't properly extend/implement the MouseListener, I stumbled upon another SO article (How can an anonymous class use "extends" or "implements"?) where I understood that anonymous Inner Classes always extend/implement a superclass (right?). So I continued my search for the answer and stumbled upon another SO article (I'm having trouble choosing when to use a MouseListener object) which is not really related to my problem, but I saw the owner of the thread write these lines of code

    @Override public void mouseExited(MouseEvent e) {}
    @Override public void mouseEntered(MouseEvent e) {}
    @Override public void mouseReleased(MouseEvent e) {}
    @Override public void mousePressed(MouseEvent e) {}

Is this what I have been missing? I already tried to @override the entire class at once but that just gave me another error on top. I can see how this would solve the problem, but it just looks very messy to me.

It basicly comes down to 2 questions; is what I've just written/discovered true, and is this the way to solve my problem and if this is the solution, is there another (cleaner) solution?