static int minXOfChildrenExcept(final Container c, Component... except) {
  final Set<Component> set = asSet(except);
  ret swing(func -> int {
    int x = c.getWidth();
    for (Component child : getChildren(c))
      if (!set.contains(child))
        x = min(x, child.getX());
    ret x;
  });
}

Began life as a copy of #1020053