Performing a Multipart Copy

If you have any questions during development, post them on the Issues page of GitHub. For details about parameters and usage of each API, see the API Reference

As a special case of multipart upload, multipart copy implements multipart upload by copying the whole or partial object in a bucket. You can call ObsClient.copyPart to copy parts. Sample code is as follows:

String endPoint = "https://your-endpoint";
String ak = "*** Provide your Access Key ***";
String sk = "*** Provide your Secret Key ***";

final String destBucketName = "destbucketname";
final String destObjectKey = "destobjectname";
final String sourceBucketName = "sourcebucketname";
final String sourceObjectKey = "sourceobjectname";
// Create an instance of ObsClient.
final ObsClient obsClient = new ObsClient(ak, sk, endPoint);

// Initialize the thread pool.
ExecutorService executorService = Executors.newFixedThreadPool(20);

// Initialize the multipart upload.
InitiateMultipartUploadRequest request = new InitiateMultipartUploadRequest(destBucketName, destObjectKey);
InitiateMultipartUploadResult result = obsClient.initiateMultipartUpload(request);

final String uploadId = result.getUploadId();
Log.i("CopyPart","\t"+ uploadId + "\n");

// Obtain information about the large object.
ObjectMetadata metadata = obsClient.getObjectMetadata(sourceBucketName, sourceObjectKey);
// Set the part size for copying to 100 MB.
long partSize = 100 * 1024 * 1024L;
long objectSize = metadata.getContentLength();

// Calculate the number of parts to be copied.
long partCount = objectSize % partSize == 0 ? objectSize / partSize : objectSize / partSize + 1;

final List<PartEtag> partEtags = Collections.synchronizedList(new ArrayList<PartEtag>());

// Concurrently copy parts.
for (int i = 0; i < partCount; i++)
{
// Start position for copying
    final long rangeStart = i * partSize;
// End position for copying
    final long rangeEnd = (i + 1 == partCount) ? objectSize - 1 : rangeStart + partSize - 1;
// Part number
    final int partNumber = i + 1;
    executorService.execute(new Runnable()
    {
        
        @Override
        public void run()
        {
            CopyPartRequest request = new CopyPartRequest();
            request.setUploadId(uploadId);
            request.setSourceBucketName(sourceBucketName);
            request.setSourceObjectKey(sourceObjectKey);
            request.setDestinationBucketName(destBucketName);
            request.setDestinationObjectKey(destObjectKey);
            request.setByteRangeStart(rangeStart);
            request.setByteRangeEnd(rangeEnd);
            request.setPartNumber(partNumber);
            CopyPartResult result;
            try
            {
                result = obsClient.copyPart(request);
                Log.i("CopyPart","Part#" + partNumber + " done\n");
                partEtags.add(new PartEtag(result.getEtag(), result.getPartNumber()));
            }
            catch (ObsException e)
            {
                Log.e("CopyPart", e.getMessage(), e);
            }
        }
    });
}

// Wait until the copy is complete.
executorService.shutdown();
while (!executorService.isTerminated())
{
    try
    {
        executorService.awaitTermination(5, TimeUnit.SECONDS);
    }
    catch (InterruptedException e)
    {
        Log.e("CopyPart", e.getMessage(), e);
    }
}

// Combine parts.
CompleteMultipartUploadRequest completeMultipartUploadRequest =
    new CompleteMultipartUploadRequest(destBucketName, destObjectKey, uploadId, partEtags);
obsClient.completeMultipartUpload(completeMultipartUploadRequest);