使用android SDK将文件直接上传到存储桶中的文件夹(Upload a file directly to a folder in bucket using android SDK)

 我使用以下代码将文件上传到S3存储桶： 
 
//upload code start
AWSCredentials credential = new BasicAWSCredentials(AppConstants.AWS_ACCESS_KEY_ID, AppConstants.AWS_SECRET_ACCESS_ID);
TransferManager manager = new TransferManager(credential);
// Transfer a file to an S3 bucket.
Upload upload = manager.upload("bucket_name", AppConstants.AWS_ACCESS_KEY_ID, file);
while (!upload.isDone()) {
    Thread.sleep(200);
}
//upload code end
 
 我想将它放入我的存储桶中名为“android_uploads”的目录中，但是传输管理器将所有文件上传到存储桶的根目录。 
 
 知道我怎么能做到这一点？ 

I am using following code to upload a file into the S3 bucket:
 
//upload code start
AWSCredentials credential = new BasicAWSCredentials(AppConstants.AWS_ACCESS_KEY_ID, AppConstants.AWS_SECRET_ACCESS_ID);
TransferManager manager = new TransferManager(credential);
// Transfer a file to an S3 bucket.
Upload upload = manager.upload("bucket_name", AppConstants.AWS_ACCESS_KEY_ID, file);
while (!upload.isDone()) {
    Thread.sleep(200);
}
//upload code end
 
I want to put this into a directory named "android_uploads" inside my bucket but Transfer Manager is uploading all the files into root of the bucket.
 
Any idea how i can achieve this?