private String defaultFormat(int n) {
		String str = "" + n;
		int availableSpace = getSize().width - 2 * PIXEL_MARGIN;
		FontMetrics fm = getFontMetrics(getFont());
		if (fm.stringWidth(str) > availableSpace) {
			str = "";
			while (fm.stringWidth(str + "#") <= availableSpace) {
				str += "#";
			}
		}
		return str;
	}