Duration duration =
                Duration.between(Instant.ofEpochMilli(resource.getTransferStartTime()), MonotonicClock.now());
        if ((duration.getSeconds() | duration.getNano()) > 0) { // duration.isPositive()
            long bytesPerSecond = Math.round(contentLength / (double) duration.toSeconds());
            message.append(" at ");
            format.format(message, bytesPerSecond);