buttonPanel.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
buttonPanel.add(clearButton);
add(buttonPanel, BorderLayout.SOUTH);
// Make the focus alternate between list and button.
FocusTraversalPolicy focusTraversalPolicy = new LayoutFocusTraversalPolicy() {
private static final long serialVersionUID = -6710851570109105533L;
@Override
public Component getComponentAfter(Container focusCycleRoot, Component aComponent) {