code: public Observable<ServiceResponse<ImportExportResponseInner>> createImportOperationWithServiceResponseAsync(String resourceGroupName, String serverName, String databaseName, ImportExtensionRequest parameters) {
          if (this.client.subscriptionId() == null) {
              throw new IllegalArgumentException("Parameter this.client.subscriptionId() is required and cannot be null.");
          }
          if (resourceGroupName == null) {
              throw new IllegalArgumentException("Parameter resourceGroupName is required and cannot be null.");
          }
          if (serverName == null) {
              throw new IllegalArgumentException("Parameter serverName is required and cannot be null.");
          }
          if (databaseName == null) {
              throw new IllegalArgumentException("Parameter databaseName is required and cannot be null.");
          }
          if (this.client.apiVersion() == null) {
              throw new IllegalArgumentException("Parameter this.client.apiVersion() is required and cannot be null.");
          }
          if (parameters == null) {
              throw new IllegalArgumentException("Parameter parameters is required and cannot be null.");
          }
          Validator.validate(parameters);
          final String extensionName = "import";
          Observable<Response<ResponseBody>> observable = service.createImportOperation(this.client.subscriptionId(), resourceGroupName, serverName, databaseName, extensionName, this.client.apiVersion(), parameters, this.client.acceptLanguage(), this.client.userAgent());
          return client.getAzureClient().getPutOrPatchResultAsync(observable, new TypeToken<ImportExportResponseInner>() { }.getType());
      }
docs: Creates an import operation that imports a bacpac into an existing database. The existing database must be empty.
  
  @param resourceGroupName The name of the resource group that contains the resource. You can obtain this value from the Azure Resource Manager API or the portal.
  @param serverName The name of the server.
  @param databaseName The name of the database to import into
  @param parameters The required parameters for importing a Bacpac into a database.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable for the request