Object Storage Service:Manage versioning (Java SDK)

Precautions

• In this topic, the public endpoint of the China (Hangzhou) region is used. To access OSS from other Alibaba Cloud services in the same region, use an internal endpoint. For details about supported regions and endpoints, see Regions and endpoints.

• In this topic, access credentials are obtained from environment variables. For more information about how to configure access credentials, see Configure access credentials.

• In this topic, an OSSClient instance is created by using an OSS endpoint. If you want to create an OSSClient instance by using custom domain names or Security Token Service (STS), see Configuration examples for common scenarios.

• To set the versioning state of a bucket, you must have the oss:PutBucketVersioning permission. To retrieve the versioning state of a bucket, you must have the oss:GetBucketVersioning permission. For more information, see Grant custom permissions to a RAM user.

Set the versioning state of a bucket

The following code provides an example of how to set the versioning state of a bucket to Enabled or Suspended.

import com.aliyun.oss.*; import com.aliyun.oss.common.auth.*; import com.aliyun.oss.common.comm.SignVersion; import com.aliyun.oss.model.*; public class Demo { public static void main(String[] args) throws Exception { // In this example, the endpoint of the China (Hangzhou) region is used. Specify the actual endpoint based on your requirements. String endpoint = "https://oss-cn-hangzhou.aliyuncs.com"; // Obtain access credentials from environment variables. Before you run this sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider(); // Specify the bucket name. Example: examplebucket. String bucketName = "examplebucket"; // Specify the region in which the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the region to cn-hangzhou. String region = "cn-hangzhou"; // Create an OSSClient instance. // When the OSSClient instance is no longer used, call the shutdown method to release the resources. ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration(); clientBuilderConfiguration.setSignatureVersion(SignVersion.V4); OSS ossClient = OSSClientBuilder.create() .endpoint(endpoint) .credentialsProvider(credentialsProvider) .clientConfiguration(clientBuilderConfiguration) .region(region) .build(); try { // Set the versioning state of the bucket to Enabled (BucketVersioningConfiguration.ENABLED). To suspend versioning for the bucket, replace BucketVersioningConfiguration.ENABLED with BucketVersioningConfiguration.SUSPENDED. BucketVersioningConfiguration configuration = new BucketVersioningConfiguration(); configuration.setStatus(BucketVersioningConfiguration.ENABLED); SetBucketVersioningRequest request = new SetBucketVersioningRequest(bucketName, configuration); ossClient.setBucketVersioning(request); } catch (OSSException oe) { System.out.println("Caught an OSSException, which means your request made it to OSS, " + "but was rejected with an error response for some reason."); System.out.println("Error Message:" + oe.getErrorMessage()); System.out.println("Error Code:" + oe.getErrorCode()); System.out.println("Request ID:" + oe.getRequestId()); System.out.println("Host ID:" + oe.getHostId()); } catch (ClientException ce) { System.out.println("Caught an ClientException, which means the client encountered " + "a serious internal problem while trying to communicate with OSS, " + "such as not being able to access the network."); System.out.println("Error Message:" + ce.getMessage()); } finally { if (ossClient != null) { ossClient.shutdown(); } } } }

Obtain information about the versioning state of a bucket

The following code provides an example of how to retrieve the versioning state of a bucket.

import com.aliyun.oss.*; import com.aliyun.oss.common.auth.*; import com.aliyun.oss.common.comm.SignVersion; import com.aliyun.oss.model.*; public class Demo { public static void main(String[] args) throws Exception { // In this example, the endpoint of the China (Hangzhou) region is used. Specify the actual endpoint based on your requirements. String endpoint = "https://oss-cn-hangzhou.aliyuncs.com"; // Obtain access credentials from environment variables. Before you run this sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider(); // Specify the bucket name. Example: examplebucket. String bucketName = "examplebucket"; // Specify the region in which the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the region to cn-hangzhou. String region = "cn-hangzhou"; // Create an OSSClient instance. // When the OSSClient instance is no longer used, call the shutdown method to release the resources. ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration(); clientBuilderConfiguration.setSignatureVersion(SignVersion.V4); OSS ossClient = OSSClientBuilder.create() .endpoint(endpoint) .credentialsProvider(credentialsProvider) .clientConfiguration(clientBuilderConfiguration) .region(region) .build(); try { // Obtain information about the versioning state of the bucket. BucketVersioningConfiguration versionConfiguration = ossClient.getBucketVersioning(bucketName); System.out.println("bucket versioning status: " + versionConfiguration.getStatus()); } catch (OSSException oe) { System.out.println("Caught an OSSException, which means your request made it to OSS, " + "but was rejected with an error response for some reason."); System.out.println("Error Message:" + oe.getErrorMessage()); System.out.println("Error Code:" + oe.getErrorCode()); System.out.println("Request ID:" + oe.getRequestId()); System.out.println("Host ID:" + oe.getHostId()); } catch (ClientException ce) { System.out.println("Caught an ClientException, which means the client encountered " + "a serious internal problem while trying to communicate with OSS, " + "such as not being able to access the network."); System.out.println("Error Message:" + ce.getMessage()); } finally { if (ossClient != null) { ossClient.shutdown(); } } } }

References

• For the complete sample code for managing versioning, see GitHub sample.

• For more information about the API operation for setting the versioning state of a bucket, see PutBucketVersioning.

• For more information about the API operation for retrieving the versioning state of a bucket, see GetBucketVersioning.