public static String convertFileSize(long size) {        long kb = 1024;        long mb = kb * 1024;        long gb = mb * 1024;         if (size >= gb) {            return String.format("%.1f GB", (float) size / gb);        } else if (size >= mb) {            float f = (float) size / mb;            return String.format(f > 100 ? "%.0f MB" : "%.1f MB", f);        } else if (size >= kb) {            float f = (float) size / kb;            return String.format(f > 100 ? "%.0f KB" : "%.1f KB", f);        } else            return String.format("%d B", size);    }