Codessentials

If you want to make a JScrollPane transparent then it's not enough to set the Opaque property of the JScrollPane itself to transparent.

You need to set the Opaque property of the viewport as well.

Example:

JPanel backplane = new JPanel(); 
JScrollPane scroller = new JScrollPane(backplane); 
scroller.setOpaque(false);
scroller.getViewport().setOpaque(false);