Load document from Azure Blob Storage

Following example demonstrates how to process documents from Azure Blob Storage.

public static void run() throws Exception
    String key = "sample.docx";
    String outputFilePath = new File(Constants.OutputPath, "SignFromStream//signedSample.docx").getPath();
    try {
        ByteArrayOutputStream stream = downloadFile(key);
        Signature signature = new Signature(new ByteArrayInputStream(stream.toByteArray()));
        QrCodeSignOptions options = new QrCodeSignOptions("JohnSmith");
        // sign document to file
        signature.sign(outputFilePath, options);
        System.out.print("\nSource document signed successfully.\nFile saved at " + outputFilePath);
    }catch(Exception e){
        throw new GroupDocsSignatureException(e.getMessage());
public static final String STORAGE_CONNECTION_STRING
        = "DefaultEndpointsProtocol=https;"
        + "AccountName=Ram;" //Your account name.
        + "AccountKey=key"; //your account key.
public static ByteArrayOutputStream downloadFile(String blobName) throws Exception
    CloudBlobContainer container = getContainer();
    CloudBlob blob = container.getBlockBlobReference(blobName);
    ByteArrayOutputStream memoryStream = new ByteArrayOutputStream();
    //memoryStream.Position = 0;
    return memoryStream;
private static CloudBlobContainer getContainer() throws Exception
    String containerName = "***";
    CloudStorageAccount cloudStorageAccount = CloudStorageAccount.parse(STORAGE_CONNECTION_STRING);
    CloudBlobClient cloudBlobClient = cloudStorageAccount.createCloudBlobClient();
    CloudBlobContainer container = cloudBlobClient.getContainerReference(containerName);
    return container;

More resources

GitHub Examples 

You may easily run the code above and see the feature in action in our GitHub examples:

Free Online App 

Along with full-featured .NET library we provide simple, but powerful free Apps.
You are welcome to eSign PDF, Word, Excel, PowerPoint documents with free to use online GroupDocs Signature App.