对象大于 5GiB 时，您可以使用 TOS Java SDK 的 uploadPartCopy 接口进行分片拷贝。
注意事项
拷贝文件不支持跨区域的桶间拷贝。
拷贝对象时，账号必须具备源对象的读取权限和目标桶的写入权限。
拷贝对象时，可以保留所有元数据（默认值）或指定新的元数据。但 ACL 并未被保留，而是设置为私有。
示例代码
以下代码展示如何将 srcBucketName 桶中的 srcObjectKey 对象分片拷贝到 bucketName 桶中，并设置对象名为 objectKey。
import com.volcengine.tos.TOSV2;​
import com.volcengine.tos.TOSV2ClientBuilder;​
import com.volcengine.tos.TosClientException;​
import com.volcengine.tos.TosServerException;​
import com.volcengine.tos.model.object.*;​
​
import java.util.ArrayList;​
import java.util.List;​
​
public class UploadPartCopyExample {​
    public static void main(String[] args) {​
        String endpoint = "your endpoint";​
        String region = "your region";​
        String accessKey = System.getenv("TOS_ACCESS_KEY");​
        String secretKey = System.getenv("TOS_SECRET_KEY");​
​
        // 源桶名​
        String srcBucketName = "src-bucket-example";​
        // 源对象名，需保证对象存在，否则报404​
        String srcObjectKey = "src_example_dir/example_object.txt";​
        // 目的桶名​
        String bucketName = "bucket-example";​
        // 目的对象名，如果目的对象存在，默认会将其覆盖​
        String objectKey = "dst_example_dir/example_object.txt";​
​
        long partSize = 10 * 1024 * 1024;​
​
        TOSV2 tos = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey);​
​
        try{​
            // 从源桶中获取待拷贝对象的大小​
            HeadObjectV2Output headInfo = tos.headObject(new HeadObjectV2Input().setBucket(srcBucketName).setKey(srcObjectKey));​
            long contentLength = headInfo.getContentLength();​
​
            // 初始化分片拷贝任务​
            CreateMultipartUploadInput create = new CreateMultipartUploadInput().setBucket(bucketName).setKey(objectKey);​
            CreateMultipartUploadOutput created = tos.createMultipartUpload(create);​
            String uploadID = created.getUploadID();​
​
            // 进行分片拷贝​
            List<UploadedPartV2> partList = new ArrayList<>();​
            // 从位置 0 开始拷贝​
            long rangeStart = 0, rangeEnd = 0;​
            int partNumber = 1;​
            while (rangeStart < contentLength) {​
                // 最长不能超过源对象长度​
                rangeEnd = Math.min(rangeStart + partSize - 1, contentLength - 1);​
                UploadPartCopyV2Input input = new UploadPartCopyV2Input().setBucket(bucketName).setKey(objectKey)​
                        .setUploadID(uploadID).setSourceBucket(srcBucketName).setSourceKey(srcObjectKey)​
                        .setPartNumber(partNumber).setCopySourceRange(rangeStart, rangeEnd);​
//                // 如果需要设置目的对象的 ACL/storageClass 等元数据，可参考以下代码​
//                ObjectMetaRequestOptions options = new ObjectMetaRequestOptions();​
//                // 指定 ACL 为 private​
//                options.setAclType(ACLType.ACL_PRIVATE);​
//                // 指定 storageClass 为标准存储​
//                options.setStorageClass(StorageClassType.STORAGE_CLASS_STANDARD);​
//                input.setOptions(options);​
//                // 指定限定条件，源对象的 ETag 与指定的 ETag 匹配时才拷贝，​
//                // 指定的 ETag 可通过 headObject 获取，此处的 "XXX" 仅为示例，请使用正确的 ETag​
//                input.setCopySourceIfMatch("XXX");​
                UploadPartCopyV2Output output = tos.uploadPartCopy(input);​
                System.out.println("uploadPartCopy succeed, part's etag is " + output.getEtag());​
                System.out.println("uploadPartCopy succeed, part's partNumber is " + output.getPartNumber());​
                partList.add(new UploadedPartV2().setEtag(output.getEtag()).setPartNumber(output.getPartNumber()));​
                rangeStart = rangeEnd + 1;​
                partNumber++;​
            }​
​
            // 合并拷贝的分片​
            CompleteMultipartUploadV2Input complete = new CompleteMultipartUploadV2Input().setBucket(bucketName)​
                    .setKey(objectKey).setUploadID(uploadID).setUploadedParts(partList);​
            CompleteMultipartUploadV2Output output = tos.completeMultipartUpload(complete);​
            System.out.println("copyObject succeed, object's etag is " + output.getEtag());​
            System.out.println("copyObject succeed, object's crc64 is " + output.getHashCrc64ecma());​
        } catch (TosClientException e) {​
            // 操作失败，捕获客户端异常，一般情况是请求参数错误，此时请求并未发送​
            System.out.println("copyObject failed");​
            System.out.println("Message: " + e.getMessage());​
            if (e.getCause() != null) {​
                e.getCause().printStackTrace();​
            }​
        } catch (TosServerException e) {​
            // 操作失败，捕获服务端异常，可以获取到从服务端返回的详细错误信息​
            System.out.println("copyObject failed");​
            System.out.println("StatusCode: " + e.getStatusCode());​
            System.out.println("Code: " + e.getCode());​
            System.out.println("Message: " + e.getMessage());​
            System.out.println("RequestID: " + e.getRequestID());​
        } catch (Throwable t) {​
            // 作为兜底捕获其他异常，一般不会执行到这里​
            System.out.println("copyObject failed");​
            System.out.println("unexpected exception, message: " + t.getMessage());​
        }​
    }​
}​
对象存储
