1      背景介绍 & 效果展示

OBS提供三种存储类型：标准存储、低频访问存储或归档存储。低频访问存储的对象可以修改为标准存储或归档存储的对象。归档存储的对象要先恢复，才可以修改为标准存储或低频访问存储。本文通过JAVA SDK实现将对象从标准存储转换为归档存储，以及归档存储到低频访问存储的转换，效果如下。

注：有关标准存储、低频访问、归档存储三种存储类型的更多信息，参考链接：https://support.huaweicloud.com/usermanual-obs/zh-cn_topic_0050321036.html

图1 原始对象

图2 对象从标准存储转换为归档存储

图3 对象从归档存储转换为低频访问存储

2      java代码参考（对象从标准存储转换为归档存储）

前提：

需要先下载OBS最新的JAVA SDK，参考官网链接：https://developer.huaweicloud.com/sdk?OBS，并在自己的项目中导入SDK中的JAR包。

       public static void main(String[] args) throws IOException {

                   // 需要将endPoint/ak/sk更新为实际信息

                   String endPoint = "https://your-endpoint";

                   String ak = "*** Provide your Access Key ***";

                   String sk = "*** Provide your Secret Key ***";

                   // 创建ObsClient实例

                   ObsClient obsClient = new ObsClient(ak, sk, endPoint);

                   try

                  {

                                      String bucketName = "bucketXXX";                // 需要将bucketName更新为实际信息

                                       String objectName = "objectXXX";                // 需要将objectName更新为实际信息

CopyObjectRequest request = new CopyObjectRequest(bucketName, objectName, bucketName, objectName);

                              request.setReplaceMetadata(true);

                                        ObjectMetadata newObjectMetadata = new ObjectMetadata();

                                        newObjectMetadata.setContentType("image/jpeg");           // 修改对象的ContentType

                                        newObjectMetadata.setObjectStorageClass(StorageClassEnum.COLD);              // 转换为归档存储

                                        request.setNewObjectMetadata(newObjectMetadata);

                                        CopyObjectResult result = obsClient.copyObject(request);

                                        System.out.println("\t" + result.getStatusCode());

                  }

                  catch (ObsException e)

                  {

                      System.out.println("Response Code: " + e.getResponseCode());

                      System.out.println("Error Message: " + e.getErrorMessage());

                      System.out.println("Error Code:       " + e.getErrorCode());

                      System.out.println("Request ID:      " + e.getErrorRequestId());

                      System.out.println("Host ID:           " + e.getErrorHostId());

                  }

}

3      java代码参考（对象从归档存储转换为低频访问存储）

前提：

需要先下载OBS最新的JAVA SDK，参考官网链接：https://developer.huaweicloud.com/sdk?OBS，并在自己的项目中导入SDK中的JAR包。

       public static void main(String[] args) throws IOException {

                   // 需要将endPoint/ak/sk更新为实际信息

                   String endPoint = "https://your-endpoint";

                   String ak = "*** Provide your Access Key ***";

                   String sk = "*** Provide your Secret Key ***";

                   // 创建ObsClient实例

                   ObsClient obsClient = new ObsClient(ak, sk, endPoint);

                   try

                  {

                                      String bucketName = "bucketXXX";                // 需要将bucketName更新为实际信息

                                       String objectName = "objectXXX";                // 需要将objectName更新为实际信息

                                        // 快速取回归档对象

RestoreObjectRequest request1 = new RestoreObjectRequest();

                                        request1.setBucketName(bucketName);

                                        request1.setObjectKey(objectName);

                                        request1.setDays(1);

                                        request1.setRestoreTier(RestoreTierEnum.EXPEDITED);

                                        obsClient.restoreObjectV2(request1);

                                        // 等待对象取回

                                        Thread.sleep(60 * 6 * 1000);

                                        CopyObjectRequest request = new CopyObjectRequest(bucketName, objectName, bucketName, objectName);

                                        ObjectMetadata newObjectMetadata = new ObjectMetadata();

                                        newObjectMetadata.setObjectStorageClass(StorageClassEnum.WARM);              // 转换为低频访问存储

                                        request.setNewObjectMetadata(newObjectMetadata);

                                        CopyObjectResult result = obsClient.copyObject(request);

                                        System.out.println("\t" + result.getStatusCode());

                  }

                  catch (ObsException e)

                  {

                      System.out.println("Response Code: " + e.getResponseCode());

                      System.out.println("Error Message: " + e.getErrorMessage());

                      System.out.println("Error Code:       " + e.getErrorCode());

                      System.out.println("Request ID:      " + e.getErrorRequestId());

                      System.out.println("Host ID:           " + e.getErrorHostId());

                  }

}

4      附录链接

OBS JAVA SDK使用方法，官网参考链接：https://support.huaweicloud.com/sdk-java-devg-obs/zh-cn_topic_0142815558.html