JDesktopPaneに配置されたすべてのJInternalFrameの表示状態を切り替える

JDesktopPane desktop = new JDesktopPane();

JToggleButton button1 = new JToggleButton("Iconify Frames");
button1.addActionListener(e -> {
  DesktopManager m = desktop.getDesktopManager();
  List<JInternalFrame> frames = Arrays.asList(desktop.getAllFrames());
  if (((AbstractButton) e.getSource()).isSelected()) {
    reverseList(frames).forEach(m::iconifyFrame);
  } else {
    // reverseList(frames).forEach(m::openFrame);
    frames.forEach(m::deiconifyFrame);
  }
});

JToggleButton button2 = new JToggleButton("Show Desktop");
button2.addActionListener(e -> {
  boolean show = ((AbstractButton) e.getSource()).isSelected();
  JInternalFrame[] frames = desktop.getAllFrames();
  // TEST: Arrays.asList(frames).forEach(f -> f.setVisible(!show));
  reverseList(Arrays.asList(frames)).forEach(f -> f.setVisible(!show));
  // for (int i = frames.length - 1; i >= 0; i--) {
  //   frames[i].setVisible(!show);
  // }
});