public static String create(final long num) {
        if (num > MAX_VAL) {
            throw new IllegalArgumentException(num + " exceeds 10 digits");
        }
        return Strings.padStart(Long.toString(num), 10, '0');
    }
Create a string to use as part of a file name that is a `0` padded number.

@param num The number to create the name from.
@return A `0` padded string representing the supplied number.
stroom-proxy/stroom-proxy-app/src/main/java/stroom/proxy/app/handler/NumericFileNameUtil.java