public final void addTo(@NotNull JComponent component) {
    List<HoverListener> list = ClientProperty.get(component, HOVER_LISTENER_LIST_KEY);
    if (list == null) {
      component.putClientProperty(HOVER_LISTENER_LIST_KEY, list = ContainerUtil.createLockFreeCopyOnWriteList());
    }
    list.add(0, this);
  }
public final void addTo(@NotNull JComponent component)