Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Performing and managing a multipart upload with the SDK for Java

With Amazon S3 on Outposts, you can create S3 buckets on your Amazon Outposts resources and store and retrieve objects on-premises for applications that require local data access, local data processing, and data residency. You can use S3 on Outposts through the Amazon Web Services Management Console, Amazon Command Line Interface (Amazon CLI), Amazon SDKs, or REST API. For more information, see What is Amazon S3 on Outposts?

The following examples show how you can use S3 on Outposts with the Amazon SDK for Java to perform and manage a multipart upload.

Perform a multipart upload of an object in an S3 on Outposts bucket

The following S3 on Outposts example initiates, uploads, and finishes a multipart upload of an object to a bucket by using the SDK for Java. To use this example, replace each user input placeholder with your own information. For more information, see Uploading an object using multipart upload.

import com.amazonaws.AmazonServiceException;
import com.amazonaws.SdkClientException;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.*;

import java.util.ArrayList;
import java.util.List;

public class MultipartUploadCopy {
    public static void main(String[] args) {
        String accessPointArn = "*** Source access point ARN ***";
        String sourceObjectKey = "*** Source object key ***";
        String destObjectKey = "*** Target object key ***";

        try {
            // This code expects that you have Amazon credentials set up per:
            // https://docs.amazonaws.cn/sdk-for-java/v1/developer-guide/setup-credentials.html
            AmazonS3 s3Client = AmazonS3ClientBuilder.standard()
                    .enableUseArnRegion()
                    .build();

            // Initiate the multipart upload.
            InitiateMultipartUploadRequest initRequest = new InitiateMultipartUploadRequest(accessPointArn, destObjectKey);
            InitiateMultipartUploadResult initResult = s3Client.initiateMultipartUpload(initRequest);

            // Get the object size to track the end of the copy operation.
            GetObjectMetadataRequest metadataRequest = new GetObjectMetadataRequest(accessPointArn, sourceObjectKey);
            ObjectMetadata metadataResult = s3Client.getObjectMetadata(metadataRequest);
            long objectSize = metadataResult.getContentLength();

            // Copy the object using 5 MB parts.
            long partSize = 5 * 1024 * 1024;
            long bytePosition = 0;
            int partNum = 1;
            List<CopyPartResult> copyResponses = new ArrayList<CopyPartResult>();
            while (bytePosition < objectSize) {
                // The last part might be smaller than partSize, so check to make sure
                // that lastByte isn't beyond the end of the object.
                long lastByte = Math.min(bytePosition + partSize - 1, objectSize - 1);

                // Copy this part.
                CopyPartRequest copyRequest = new CopyPartRequest()
                        .withSourceBucketName(accessPointArn)
                        .withSourceKey(sourceObjectKey)
                        .withDestinationBucketName(accessPointArn)
                        .withDestinationKey(destObjectKey)
                        .withUploadId(initResult.getUploadId())
                        .withFirstByte(bytePosition)
                        .withLastByte(lastByte)
                        .withPartNumber(partNum++);
                copyResponses.add(s3Client.copyPart(copyRequest));
                bytePosition += partSize;
            }

            // Complete the upload request to concatenate all uploaded parts and make the copied object available.
            CompleteMultipartUploadRequest completeRequest = new CompleteMultipartUploadRequest(
                    accessPointArn,
                    destObjectKey,
                    initResult.getUploadId(),
                    getETags(copyResponses));
            s3Client.completeMultipartUpload(completeRequest);
            System.out.println("Multipart copy complete.");
        } catch (AmazonServiceException e) {
            // The call was transmitted successfully, but Amazon S3 couldn't process 
            // it, so it returned an error response.
            e.printStackTrace();
        } catch (SdkClientException e) {
            // Amazon S3 couldn't be contacted for a response, or the client  
            // couldn't parse the response from Amazon S3.
            e.printStackTrace();
        }
    }

    // This is a helper function to construct a list of ETags.
    private static List<PartETag> getETags(List<CopyPartResult> responses) {
        List<PartETag> etags = new ArrayList<PartETag>();
        for (CopyPartResult response : responses) {
            etags.add(new PartETag(response.getPartNumber(), response.getETag()));
        }
        return etags;
    }

Copy a large object in an S3 on Outposts bucket by using multipart upload

The following S3 on Outposts example uses the SDK for Java to copy an object in a bucket. To use this example, replace each user input placeholder with your own information. This example is adapted from Copying an object using multipart upload.

import com.amazonaws.AmazonServiceException;
import com.amazonaws.SdkClientException;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.*;

import java.util.ArrayList;
import java.util.List;

public class MultipartUploadCopy {
    public static void main(String[] args) {
        String accessPointArn = "*** Source access point ARN ***";
        String sourceObjectKey = "*** Source object key ***";
        String destObjectKey = "*** Target object key ***";

        try {
            // This code expects that you have Amazon credentials set up per:
            // https://docs.amazonaws.cn/sdk-for-java/v1/developer-guide/setup-credentials.html
            AmazonS3 s3Client = AmazonS3ClientBuilder.standard()
                    .enableUseArnRegion()
                    .build();

            // Initiate the multipart upload.
            InitiateMultipartUploadRequest initRequest = new InitiateMultipartUploadRequest(accessPointArn, destObjectKey);
            InitiateMultipartUploadResult initResult = s3Client.initiateMultipartUpload(initRequest);

            // Get the object size to track the end of the copy operation.
            GetObjectMetadataRequest metadataRequest = new GetObjectMetadataRequest(accessPointArn, sourceObjectKey);
            ObjectMetadata metadataResult = s3Client.getObjectMetadata(metadataRequest);
            long objectSize = metadataResult.getContentLength();

            // Copy the object using 5 MB parts.
            long partSize = 5 * 1024 * 1024;
            long bytePosition = 0;
            int partNum = 1;
            List<CopyPartResult> copyResponses = new ArrayList<CopyPartResult>();
            while (bytePosition < objectSize) {
                // The last part might be smaller than partSize, so check to make sure
                // that lastByte isn't beyond the end of the object.
                long lastByte = Math.min(bytePosition + partSize - 1, objectSize - 1);

                // Copy this part.
                CopyPartRequest copyRequest = new CopyPartRequest()
                        .withSourceBucketName(accessPointArn)
                        .withSourceKey(sourceObjectKey)
                        .withDestinationBucketName(accessPointArn)
                        .withDestinationKey(destObjectKey)
                        .withUploadId(initResult.getUploadId())
                        .withFirstByte(bytePosition)
                        .withLastByte(lastByte)
                        .withPartNumber(partNum++);
                copyResponses.add(s3Client.copyPart(copyRequest));
                bytePosition += partSize;
            }

            // Complete the upload request to concatenate all uploaded parts and make the copied object available.
            CompleteMultipartUploadRequest completeRequest = new CompleteMultipartUploadRequest(
                    accessPointArn,
                    destObjectKey,
                    initResult.getUploadId(),
                    getETags(copyResponses));
            s3Client.completeMultipartUpload(completeRequest);
            System.out.println("Multipart copy complete.");
        } catch (AmazonServiceException e) {
            // The call was transmitted successfully, but Amazon S3 couldn't process 
            // it, so it returned an error response.
            e.printStackTrace();
        } catch (SdkClientException e) {
            // Amazon S3 couldn't be contacted for a response, or the client  
            // couldn't parse the response from Amazon S3.
            e.printStackTrace();
        }
    }

    // This is a helper function to construct a list of ETags.
    private static List<PartETag> getETags(List<CopyPartResult> responses) {
        List<PartETag> etags = new ArrayList<PartETag>();
        for (CopyPartResult response : responses) {
            etags.add(new PartETag(response.getPartNumber(), response.getETag()));
        }
        return etags;
    }
}

List parts of an object in an S3 on Outposts bucket

The following S3 on Outposts example lists the parts of an object in a bucket by using the SDK for Java. To use this example, replace each user input placeholder with your own information.

import com.amazonaws.AmazonServiceException;
import com.amazonaws.SdkClientException;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.*;

import java.util.List;

public class ListParts {
    public static void main(String[] args) {
        String accessPointArn = "*** access point ARN ***";
        String keyName = "*** Key name ***";
        String uploadId = "*** Upload ID ***";

        try {
            // This code expects that you have Amazon credentials set up per:
            // https://docs.amazonaws.cn/sdk-for-java/v1/developer-guide/setup-credentials.html
            AmazonS3 s3Client = AmazonS3ClientBuilder.standard()
                    .enableUseArnRegion()
                    .build();

            ListPartsRequest listPartsRequest = new ListPartsRequest(accessPointArn, keyName, uploadId);
            PartListing partListing = s3Client.listParts(listPartsRequest);
            List<PartSummary> partSummaries = partListing.getParts();

            System.out.println(partSummaries.size() + " multipart upload parts");
            for (PartSummary p : partSummaries) {
                System.out.println("Upload part: Part number = \"" + p.getPartNumber() + "\", ETag = " + p.getETag());
            }

        } catch (AmazonServiceException e) {
            // The call was transmitted successfully, but Amazon S3 couldn't process
            // it, so it returned an error response.
            e.printStackTrace();
        } catch (SdkClientException e) {
            // Amazon S3 couldn't be contacted for a response, or the client
            // couldn't parse the response from Amazon S3.
            e.printStackTrace();
        }
    }
}

Retrieve a list of in-progress multipart uploads in an S3 on Outposts bucket

The following S3 on Outposts example shows how to retrieve a list of the in-progress multipart uploads from an Outposts bucket by using the SDK for Java. To use this example, replace each user input placeholder with your own information. This example is adapted from the Listing multipart uploads example for Amazon S3.

import com.amazonaws.AmazonServiceException;
import com.amazonaws.SdkClientException;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.ListMultipartUploadsRequest;
import com.amazonaws.services.s3.model.MultipartUpload;
import com.amazonaws.services.s3.model.MultipartUploadListing;

import java.util.List;

public class ListMultipartUploads {
    public static void main(String[] args) {
                String accessPointArn = "*** access point ARN ***";

        try {
            // This code expects that you have Amazon credentials set up per:
            // https://docs.amazonaws.cn/sdk-for-java/v1/developer-guide/setup-credentials.html
            AmazonS3 s3Client = AmazonS3ClientBuilder.standard()
                    .enableUseArnRegion()
                    .build();

            // Retrieve a list of all in-progress multipart uploads.
            ListMultipartUploadsRequest allMultipartUploadsRequest = new ListMultipartUploadsRequest(accessPointArn);
            MultipartUploadListing multipartUploadListing = s3Client.listMultipartUploads(allMultipartUploadsRequest);
            List<MultipartUpload> uploads = multipartUploadListing.getMultipartUploads();

            // Display information about all in-progress multipart uploads.
            System.out.println(uploads.size() + " multipart upload(s) in progress.");
            for (MultipartUpload u : uploads) {
                System.out.println("Upload in progress: Key = \"" + u.getKey() + "\", id = " + u.getUploadId());
            }
        } catch (AmazonServiceException e) {
            // The call was transmitted successfully, but Amazon S3 couldn't process
            // it, so it returned an error response.
            e.printStackTrace();
        } catch (SdkClientException e) {
            // Amazon S3 couldn't be contacted for a response, or the client
            // couldn't parse the response from Amazon S3.
            e.printStackTrace();
        }
    }
}