void (@Nullable Component c) { if (c == null) return; if (c instanceof RootPaneContainer) { JRootPane rootPane = ((RootPaneContainer)c).getRootPane(); if (rootPane != null) { ComponentUtil.decorateWindowHeader(rootPane); } } for (Component component : UIUtil.uiTraverser(c).postOrderDfsTraversal()) { if (component instanceof JComponent) ((JComponent)component).updateUI(); } c.invalidate(); c.validate(); c.repaint(); }