Map<String, Object> metadata = new HashMap<String, Object>();
metadata.put("test-md-value", "testing, testing, 123");
metadata.put("test-timestamp-value", System.currentTimeMillis());
// Start a multipart upload
MultipartUpload testMultipartUpload = service.multipartStartUpload(
bucketName, objectKey, metadata,
AccessControlList.REST_CANNED_AUTHENTICATED_READ, null);
assertEquals(bucketName, testMultipartUpload.getBucketName());
assertEquals(objectKey, testMultipartUpload.getObjectKey());