public static String computeBucketedFileName(String queryId, int bucket)
    {
        String paddedBucket = Strings.padStart(Integer.toString(bucket), BUCKET_NUMBER_PADDING, '0');
        return format("0%s_0_%s", paddedBucket, queryId);
    }
@Test
    public void testComputeBucketedFileName()
    {
        String name = computeBucketedFileName("20180102_030405_00641_x1y2z", 1234);
        assertEquals(name, "001234_0_20180102_030405_00641_x1y2z");
        assertEquals(getBucketIdFromFile(name), 1234);
    }