How Do I Perform Batch Operations Using the SDK?

Sample Code 1: Uploading Objects in Batches

The following code shows how to upload objects in batches.

// Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK and store them in the configuration file or environment variables.
// In this example, the AK and SK are stored in environment variables. Before running this example, configure environment variables ACCESS_KEY_ID and SECRET_ACCESS_KEY_ID.
// Obtain an AK/SK pair on the management console.
String ak = System.getenv("ACCESS_KEY_ID");
String sk = System.getenv("SECRET_ACCESS_KEY_ID");
String endPoint = "https://your-endpoint";

// Create an ObsClient instance.
ObsClient obsClient = new ObsClient(ak, sk, endPoint);

try {
    String bucketName = "examplebucket";
    // Define the prefix of objects in a bucket.
    String objectPre = "object/";
    // Folder to be uploaded
    String localDirPath = Environment.getExternalStorageDirectory().getAbsolutePath() + "/localDirPath";

    // Traverse the local folder and upload files one by one.
    File localDir = new File(localDirPath);
    if (localDir != null && localDir.isDirectory()) {
        File[] files = localDir.listFiles();
        if (files != null) {
            int succeedCount = 0;
            int failCount = 0;
            for (File file : files) {
                if (file.isFile()) {
                    try {
                        String objectKey = objectPre + file.getName();
                        PutObjectResult result = obsClient.putObject(bucketName, objectKey, file);
                        Log.i("BatchUpload", "Upload succeeded: " + objectKey);
                        succeedCount++;
                    } catch (ObsException e) {
                        Log.e("BatchUpload", "Upload failed: " + file.getName()
                                + ", Error Code: " + e.getErrorCode()
                                + ", Error Message: " + e.getErrorMessage());
                        failCount++;
                    }
                }
            }
            Log.i("BatchUpload", "Batch upload completed. Succeed: " + succeedCount + ", Failed: " + failCount);
        }
    }
} catch (ObsException e) {
    Log.e("BatchUpload", "Response Code: " + e.getResponseCode());
    Log.e("BatchUpload", "Error Message: " + e.getErrorMessage());
    Log.e("BatchUpload", "Error Code:    " + e.getErrorCode());
    Log.e("BatchUpload", "Request ID:    " + e.getErrorRequestId());
    Log.e("BatchUpload", "Host ID:       " + e.getErrorHostId());
} catch (Exception e) {
    Log.e("BatchUpload", "batch upload failed: " + e.getMessage());
}

• Network operations must be performed in child threads. Do not call the preceding code in the main thread (UI thread). Otherwise, the NetworkOnMainThreadException exception will be thrown.
• If there are a large number of local files or the files are large, you are advised to use multiple threads to upload files concurrently to improve efficiency.
• To upload files in subfolders, you need to recursively traverse the directory structure.
• If the size of the file to be uploaded is large, you can use the resumable upload API (uploadFile) to replace the object upload API (putObject).

Sample Code 2: Downloading Objects in Batches

The following code shows how to download objects in batches.

// Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK and store them in the configuration file or environment variables.
// In this example, the AK and SK are stored in environment variables. Before running this example, configure environment variables ACCESS_KEY_ID and SECRET_ACCESS_KEY_ID.
// Obtain an AK/SK pair on the management console.
String ak = System.getenv("ACCESS_KEY_ID");
String sk = System.getenv("SECRET_ACCESS_KEY_ID");
String endPoint = "https://your-endpoint";

// Create an ObsClient instance.
final ObsClient obsClient = new ObsClient(ak, sk, endPoint);

try {
    String bucketName = "examplebucket";
    String objectPre = "object/";
    // Local download directory
    String localDownloadDir = Environment.getExternalStorageDirectory().getAbsolutePath() + "/download";

    // 1. List all objects with a specified prefix in the bucket.
    ListObjectsRequest listRequest = new ListObjectsRequest(bucketName);
    listRequest.setPrefix(objectPre);
    ObjectListing result = obsClient.listObjects(listRequest);

    // 2. Download objects one by one.
    for (ObsObject obsObject : result.getObjects()) {
        String objectKey = obsObject.getObjectKey();
        // Skip folders (objects whose names end with a slash (/)).
        if (objectKey.endsWith("/")) {
            continue;
        }
        // Generate local file paths.
        String localFilePath = localDownloadDir + "/" + objectKey.substring(objectPre.length());
        DownloadFileRequest downloadRequest = new DownloadFileRequest(bucketName, objectKey);
        downloadRequest.setDownloadFile(localFilePath);
        obsClient.downloadFile(downloadRequest);
        Log.i("BatchDownload", "Downloaded: " + objectKey);
    }
    Log.i("BatchDownload", "Batch download completed");
} catch (ObsException e) {
    Log.e("BatchDownload", "Response Code: " + e.getResponseCode());
    Log.e("BatchDownload", "Error Message: " + e.getErrorMessage());
    Log.e("BatchDownload", "Error Code:    " + e.getErrorCode());
    Log.e("BatchDownload", "Request ID:    " + e.getErrorRequestId());
    Log.e("BatchDownload", "Host ID:       " + e.getErrorHostId());
} catch (Exception e) {
    Log.e("BatchDownload", "Batch download failed: " + e.getMessage());
}

• Network operations must be performed in child threads. Do not call the preceding code in the main thread (UI thread). Otherwise, the NetworkOnMainThreadException exception will be thrown.
• You can use multiple threads to concurrently download objects to improve efficiency.
• If there are a large number of objects in the bucket, you need to list all objects in pagination mode. For details, see Listing Objects.

Sample Code 3: Copying Objects in Batches

The following code shows how to copy objects in batches.

// Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK and store them in the configuration file or environment variables.
// In this example, the AK and SK are stored in environment variables. Before running this example, configure environment variables ACCESS_KEY_ID and SECRET_ACCESS_KEY_ID.
// Obtain an AK/SK pair on the management console.
String ak = System.getenv("ACCESS_KEY_ID");
String sk = System.getenv("SECRET_ACCESS_KEY_ID");
String endPoint = "https://your-endpoint";

// Create an ObsClient instance.
ObsClient obsClient = new ObsClient(ak, sk, endPoint);

try {
    String sourceBucketName = "examplebucket";
    String destBucketName = "destbucket";
    String objectPre = "object/";

    // 1. List all objects with a specified prefix in the source bucket.
    ListObjectsRequest listRequest = new ListObjectsRequest(sourceBucketName);
    listRequest.setPrefix(objectPre);
    ObjectListing result = obsClient.listObjects(listRequest);

    // 2. Copy objects one by one.
    for (ObsObject obsObject : result.getObjects()) {
        String objectKey = obsObject.getObjectKey();
        // Skip folders.
        if (objectKey.endsWith("/")) {
            continue;
        }
        CopyObjectRequest copyRequest = new CopyObjectRequest(sourceBucketName, objectKey, destBucketName, objectKey);
        obsClient.copyObject(copyRequest);
        Log.i("BatchCopy", "Copied: " + objectKey);
    }
    Log.i("BatchCopy", "Batch copy completed");
} catch (ObsException e) {
    Log.e("BatchCopy", "Response Code: " + e.getResponseCode());
    Log.e("BatchCopy", "Error Message: " + e.getErrorMessage());
    Log.e("BatchCopy", "Error Code:    " + e.getErrorCode());
    Log.e("BatchCopy", "Request ID:    " + e.getErrorRequestId());
    Log.e("BatchCopy", "Host ID:       " + e.getErrorHostId());
} catch (Exception e) {
    Log.e("BatchCopy", "Batch copy failed: " + e.getMessage());
}

• Network operations must be performed in child threads. Do not call the preceding code in the main thread (UI thread). Otherwise, the NetworkOnMainThreadException exception will be thrown.
• If there are a large number of objects in the bucket, you need to list all objects in pagination mode. For details, see Listing Objects.

Sample Code 4: Restoring Objects in Batches

The following code shows how to restore objects with a specified prefix in batches.

// Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK and store them in the configuration file or environment variables.
// In this example, the AK and SK are stored in environment variables. Before running this example, configure environment variables ACCESS_KEY_ID and SECRET_ACCESS_KEY_ID.
// Obtain an AK/SK pair on the management console.
String ak = System.getenv("ACCESS_KEY_ID");
String sk = System.getenv("SECRET_ACCESS_KEY_ID");
String endPoint = "https://your-endpoint";

// Create an ObsClient instance.
ObsClient obsClient = new ObsClient(ak, sk, endPoint);

try {
    String bucketName = "examplebucket";
    String objectPre = "object/";

    // 1. List all objects with a specified prefix in the bucket.
    ListObjectsRequest listRequest = new ListObjectsRequest(bucketName);
    listRequest.setPrefix(objectPre);
    ObjectListing listing = obsClient.listObjects(listRequest);

    // 2. Restore Archive or Deep Archive objects one by one.
    int succeedCount = 0;
    int failCount = 0;
    for (ObsObject obsObject : listing.getObjects()) {
        String objectKey = obsObject.getObjectKey();
        // Skip folders (objects whose names end with a slash (/)).
        if (objectKey.endsWith("/")) {
            continue;
        }
        try {
            RestoreObjectRequest request = new RestoreObjectRequest();
            request.setBucketName(bucketName);
            request.setObjectKey(objectKey);
            // Set the retention period of the restored objects.
            request.setRestoreDays(7);
            // Set the restoration speed to the standard mode.
            request.setTier(RestoreTierEnum.STANDARD);

            obsClient.restoreObject(request);
            Log.i("BatchRestore", "Restore succeeded: " + objectKey);
            succeedCount++;
        } catch (ObsException e) {
            Log.e("BatchRestore", "Restore failed: " + objectKey
                    + ", Error Code: " + e.getErrorCode()
                    + ", Error Message: " + e.getErrorMessage());
            failCount++;
        }
    }
    Log.i("BatchRestore", "Batch restore completed. Succeed: " + succeedCount + ", Failed: " + failCount);
} catch (ObsException e) {
    Log.e("BatchRestore", "Response Code: " + e.getResponseCode());
    Log.e("BatchRestore", "Error Message: " + e.getErrorMessage());
    Log.e("BatchRestore", "Error Code:    " + e.getErrorCode());
    Log.e("BatchRestore", "Request ID:    " + e.getErrorRequestId());
    Log.e("BatchRestore", "Host ID:       " + e.getErrorHostId());
} catch (Exception e) {
    Log.e("BatchRestore", "batch restore failed: " + e.getMessage());
}

The following code shows how to restore objects in batches by object name list.

// Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK and store them in the configuration file or environment variables.
// In this example, the AK and SK are stored in environment variables. Before running this example, configure environment variables ACCESS_KEY_ID and SECRET_ACCESS_KEY_ID.
// Obtain an AK/SK pair on the management console.
String ak = System.getenv("ACCESS_KEY_ID");
String sk = System.getenv("SECRET_ACCESS_KEY_ID");
String endPoint = "https://your-endpoint";

// Create an ObsClient instance.
ObsClient obsClient = new ObsClient(ak, sk, endPoint);

try {
    String bucketName = "examplebucket";
    // List of objects to be restored
    String[] objectKeys = {"objectname1", "objectname2", "objectname3"};

    int succeedCount = 0;
    int failCount = 0;
    for (String objectKey : objectKeys) {
        try {
            RestoreObjectRequest request = new RestoreObjectRequest();
            request.setBucketName(bucketName);
            request.setObjectKey(objectKey);
            // Set the retention period of the restored objects.
            request.setRestoreDays(1);
            // Set the restoration speed to the expedited mode.
            request.setTier(RestoreTierEnum.EXPEDITED);

            obsClient.restoreObject(request);
            Log.i("BatchRestore", "Restore succeeded: " + objectKey);
            succeedCount++;
        } catch (ObsException e) {
            Log.e("BatchRestore", "Restore failed: " + objectKey
                    + ", Error Code: " + e.getErrorCode()
                    + ", Error Message: " + e.getErrorMessage());
            failCount++;
        }
    }
    Log.i("BatchRestore", "Batch restore completed. Succeed: " + succeedCount + ", Failed: " + failCount);
} catch (Exception e) {
    Log.e("BatchRestore", "batch restore failed: " + e.getMessage());
}

• Network operations must be performed in child threads. Do not call the preceding code in the main thread (UI thread). Otherwise, the NetworkOnMainThreadException exception will be thrown.
• If there are a large number of objects in the bucket, you need to list all objects in pagination mode. For details, see Listing Objects.