Java uppgift

public static String format(String ocr, int gruppering) {
		String formatOcr = "";
		for(int i = 0; i < ocr.length(); i += gruppering) {
			formatOcr = formatOcr + ocr.substring(i, i+gruppering) + " ";
		}
		return formatOcr;
	}

 public static void main(String[] args) {
        for (String part : getParts("1021054087", 2)) {
            System.out.println(part);
        }
    }
    private static List<String> getParts(String string, int partitionSize) {
        List<String> parts = new ArrayList<String>();
        int len = string.length();
        for (int i=0; i<len; i+=partitionSize)
        {
            parts.add(string.substring(i, Math.min(len, i + partitionSize)));
        }
        return parts;
    }