public PositionField(Position initialValue, boolean[] active, Color bg, String fieldTitle) {
        if ((active == null) || (active.length != 9)) {
            throw new IllegalArgumentException();
        }

        if (bg == null) {
            bg = Color.WHITE;
        }

        if (fieldTitle == null) {
            fieldTitle = "";
        }

        create(initialValue, active, bg, fieldTitle);
    }