public static void ClassInitialize()
{
//get a OSS client object
_ossClient = OssClientFactory.CreateOssClient();
//get current class name, which is prefix of bucket/object
_className = TestContext.CurrentContext.Test.FullName;
_className = _className.Substring(_className.LastIndexOf('.') + 1).ToLowerInvariant();
//create the bucket
_bucketName = OssTestUtils.GetBucketName(_className);
_ossClient.CreateBucket(_bucketName);
//create sample object
_objectKey = OssTestUtils.GetObjectKey(_className);
var poResult = OssTestUtils.UploadObject(_ossClient, _bucketName, _objectKey,
Config.UploadTestFile, new ObjectMetadata());
_objectETag = poResult.ETag;
}