A forma mais adequada para trabalhar com hotkeys é assim:
public class Scrap {
public static void main(String[] args) {
final JFrame frame = new JFrame();
final JPanel panel = new JPanel();
frame.add(panel);
panel.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke(KeyEvent.VK_F1, 0), "minimizeFrame");
panel.getActionMap().put("minimizeFrame", new AbstractAction() {
public void actionPerformed(ActionEvent e) {
frame.setVisible(false);
}
});
frame.setVisible(true);
panel.requestFocus();
}
}