this ();
visible = false;   focusCycleRoot = true; setLayout(new BorderLayout());
  public Window(Window owner, GraphicsConfiguration gc)  {    this ();    synchronized (getTreeLock())      {	if (owner == null)	  throw new IllegalArgumentException ("owner must not be null");	parent = owner;        owner.ownedWindows.add(new WeakReference(this));      }    // FIXME: make this text visible in the window.    SecurityManager s = System.getSecurityManager();    if (s != null && ! s.checkTopLevelWindow(this))      warningString = System.getProperty("awt.appletWarning");    if (gc != null        && gc.getDevice().getType() != GraphicsDevice.TYPE_RASTER_SCREEN)      throw new IllegalArgumentException ("gc must be from a screen device");    if (gc == null)      graphicsConfiguration = GraphicsEnvironment.getLocalGraphicsEnvironment()                                                 .getDefaultScreenDevice()                                                 .getDefaultConfiguration();    else      graphicsConfiguration = gc;  }