Add a MouseListener to the JList. Something like:
list.addMouseListener( new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
if ( SwingUtilities.isRightMouseButton(e) )
{
JList list = (JList)e.getSource();
int row = list.locationToIndex(e.getPoint());
list.setSelectedIndex(row);
}
}
});