Manage directories using OSS SDK for Java

Usage notes

• 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, see Configure access credentials.

• This topic demonstrates creating an OSSClient instance with an OSS endpoint. For alternative configurations, such as using a custom domain or authenticating with credentials from Security Token Service (STS), see Client configuration.

Create a directory

以下代码用于创建目录。

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.PutObjectRequest;
import java.io.ByteArrayInputStream;

public class Demo {

    public static void main(String[] args) throws Exception {
        // Endpoint以华东1（杭州）为例，其它Region请按实际情况填写。
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // 从环境变量中获取访问凭证。运行本代码示例之前，请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // 填写Bucket名称，例如examplebucket。
        String bucketName = "examplebucket";
        // 填写目录名称，目录需以正斜线结尾。
        String objectName = "exampledir/";
        // 填写Bucket所在地域。以华东1（杭州）为例，Region填写为cn-hangzhou。
        String region = "cn-hangzhou";

        // 创建OSSClient实例。
        // 当OSSClient实例不再使用时，调用shutdown方法以释放资源。
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {               
            String content = "";

            // 创建PutObjectRequest对象。       
            PutObjectRequest putObjectRequest = new PutObjectRequest(bucketName, objectName, new ByteArrayInputStream(content.getBytes()));
            
            // 如果需要上传时设置存储类型和访问权限，请参考以下示例代码。
            // ObjectMetadata metadata = new ObjectMetadata();
            // metadata.setHeader(OSSHeaders.OSS_STORAGE_CLASS, StorageClass.Standard.toString());
            // metadata.setObjectAcl(CannedAccessControlList.Private);
            // putObjectRequest.setMetadata(metadata);

            // 上传字符串。
            ossClient.putObject(putObjectRequest);
        } 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();
            }
        }
    }
}

Delete a directory

When you delete objects, you can specify a prefix that is contained in the names of all objects you want to delete. In this case, the directory whose name contains the specified prefix and all objects in the directory are deleted. For example, to delete the log directory and all objects in the directory from examplebucket, you can set the prefix to log/.

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.*;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.List;

public class Demo {

    public static void main(String[] args) throws Exception {
        // yourEndpoint填写Bucket所在地域对应的Endpoint。以华东1（杭州）为例，Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // 从环境变量中获取访问凭证。运行本代码示例之前，请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // 填写Bucket名称，例如examplebucket。
        String bucketName = "examplebucket";

        // 填写待删除目录的完整路径，完整路径中不包含Bucket名称。
        final String prefix = "exampledir/";
        // 填写Bucket所在地域。以华东1（杭州）为例，Region填写为cn-hangzhou。
        String region = "cn-hangzhou";

        // 创建OSSClient实例。
        // 当OSSClient实例不再使用时，调用shutdown方法以释放资源。
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // 删除目录及目录下的所有文件。
            String nextMarker = null;
            ObjectListing objectListing = null;
            do {
                ListObjectsRequest listObjectsRequest = new ListObjectsRequest(bucketName)
                        .withPrefix(prefix)
                        .withMarker(nextMarker);

                objectListing = ossClient.listObjects(listObjectsRequest);
                if (objectListing.getObjectSummaries().size() > 0) {
                    List<String> keys = new ArrayList<String>();
                    for (OSSObjectSummary s : objectListing.getObjectSummaries()) {
                        System.out.println("key name: " + s.getKey());
                        keys.add(s.getKey());
                    }
                    DeleteObjectsRequest deleteObjectsRequest = new DeleteObjectsRequest(bucketName).withKeys(keys).withEncodingType("url");
                    DeleteObjectsResult deleteObjectsResult = ossClient.deleteObjects(deleteObjectsRequest);
                    List<String> deletedObjects = deleteObjectsResult.getDeletedObjects();
                    try {
                        for(String obj : deletedObjects) {
                            String deleteObj =  URLDecoder.decode(obj, "UTF-8");
                            System.out.println(deleteObj);
                        }
                    } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }
                }

                nextMarker = objectListing.getNextMarker();
            } while (objectListing.isTruncated());
        } 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 more information about the API operations that you can call to create a directory, see PutObject.

• For more information about the API operations that you can call to delete a directory, see DeleteObject.