code: @BetaApi(
        "The surface for long-running operations is not stable yet and may change in the future.")
    public final OperationFuture<ExportAssetsResponse, ExportAssetsRequest> exportAssetsAsync(
        ExportAssetsRequest request) {
      return exportAssetsOperationCallable().futureCall(request);
    }
docs: Exports assets with time and resource types to a given Cloud Storage location. The output
  format is newline-delimited JSON. This API implements the
  [google.longrunning.Operation][google.longrunning.Operation] API allowing you to keep track of
  the export.
  
  <p>Sample code:
  
  <pre><code>
  try (AssetServiceClient assetServiceClient = AssetServiceClient.create()) {
  ProjectName parent = ProjectName.of("[PROJECT]");
  OutputConfig outputConfig = OutputConfig.newBuilder().build();
  ExportAssetsRequest request = ExportAssetsRequest.newBuilder()
  .setParent(parent.toString())
  .setOutputConfig(outputConfig)
  .build();
  ExportAssetsResponse response = assetServiceClient.exportAssetsAsync(request).get();
  }
  </code></pre>
  
  @param request The request object containing all of the parameters for the API call.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails