Best way to get a border around a TableListBox?

I want to have a border around the list portion of the TableListBox. My table header component is all transparent except for the column labels. I don’t want the border to extend into the header.

I just want the border to include the areas where cells can appear (i.e. the bounds of the TableListBox, excluding the portion covered by the header).

What’s the cleanest way of doing this?

You’ve got an extraordinary talent for finding perfectly reasonable use-cases that just don’t quite fit into the way I’ve designed things!

I guess the least intrusive way would be to add a transparent border around the whole thing, and then in paintOverChildren(), just draw the rectangle yourself in the place that you want it, drawing over the bottom of the header component.