Performing a Multipart Copy
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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);
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