if (areaSubList != null) { areaSubList.clear(); areaSubList = null; } if (edgeSubList != null) { edgeSubList.clear(); edgeSubList = null; } if (textSubList != null) { textSubList.clear(); textSubList = null; } if (pointSubList != null) { pointSubList.clear(); pointSubList = null; }
    public void clear() {        graphics.clear();    }