Swing/AWT/SWT :: Tandem Scrolling Of JTables

I would like to have one horizontal scrollbar control the scrolling of two JScrollPane objects (each of which contains a JTable with similar models). The line of code that I hoped would give me what I want is this:

spUpper.setHorizontalScrollBar(spLower.getHorizontalScrollBar());

It does exactly what I want, except that the scrollbar appears on-screen in the spUpper JScrollPane, while the spLower JScrollPane no longer displays a scrollbar at all. That's the opposite of what I expected. Apparently, spUpper's setHorizontalScrollBar is "stealing" spLower's scrollbar.

An alternative is just to have each scrollbar use the same model, like this:

spUpper.getHorizontalScrollBar().setModel(spLower.getHorizontalScrollBar().getModel());

This links the two scrollbars such that either will control both JScrollPanes (and also the other scrollbar), but it leaves them both visible, which is not what I want. I would have thought this line would make one of them invisible:

spUpper.getHorizontalScrollBar().setVisible(false);

However, it seems to have no effect.

The full code using the first approach is below. My questions are these:

Am I correct that setHorizontalScrollBar not only sets which JScrollBar will control a JScrollPane, but also determines where it appears on the screen?If so, what happens to the original JScrollBar? Is it replaced or am I drawing one on top of the other (or something else)?Why doesn't setVisible(false) make the scrollbar disappear (and how can I do that)?

package tandemtables;
public class Main extends javax.swing.JFrame
{
public Main()

[Code].....