ListObjectsRequest listObjectsRequest = new ListObjectsRequest()
            .withBucketName(bucketName)
            .withPrefix(s3BucketKey)
            .withMaxKeys(1000)
            .withDelimiter("/");
        ObjectListing objectListing = amazonS3Client.listObjects(listObjectsRequest);
        ImmutableList.Builder<String> builder = ImmutableList.builder();