How to draw outline to selected shape in awt paint canvas java

I am making shape in java like rectangle, ecllipse using java awt paint canvas using interface Ishape that has function's like paint(Graphics g), getx(), gety(), finalpoint(), startpoint(), height(x), width (x) and so on.

Now in another class I am selecting particular shape and adding that into an array list. Now I want to add the border to that selected shape what can I do?