void (boolean next) { List<JButton> buttons = new ArrayList<>(myButtonMap.values()); int focusedIndex = ContainerUtil.indexOf(buttons, (Condition<? super Component>)Component::hasFocus); if (focusedIndex >= 0) { getEnabledIndexCyclic(buttons, focusedIndex, next).ifPresent(i -> buttons.get(i).requestFocus()); } }