Graphics rotation in Swing

I've searched online and cannot find an answer. Do any of you know how to rotate a shape in Swing?

The only thing I found was something involving this, but I have not seen something like this before:

Java Code:

    Graphics2D g2d = (Graphics2D)g;

I see this is an object reference, but what is on the right side? Does not seem like a method, as it would not equal a method nor would the parentheses be on the left. Why are parentheses there? Thanks

EDIT: Disregarding the above code, I would like to know how to rotate without Graphics 2d

Also, with G2D you it will not allow for setting x coords