public final OperationFuture<CustomClass, OperationMetadata> updateCustomClassAsync(
      CustomClass customClass, FieldMask updateMask) {
    UpdateCustomClassRequest request =
        UpdateCustomClassRequest.newBuilder()
            .setCustomClass(customClass)
            .setUpdateMask(updateMask)
            .build();
    return updateCustomClassAsync(request);
  }
Updates the [CustomClass][google.cloud.speech.v2.CustomClass].

<p>Sample code:

<pre>{@code
// This snippet has been automatically generated and should be regarded as a code template only.
// It will require modifications to work:
// - It may require correct/in-range values for request initialization.
// - It may require specifying regional endpoints when creating the service client as shown in
// https://cloud.google.com/java/docs/setup#configure_endpoints_for_the_client_library
try (SpeechClient speechClient = SpeechClient.create()) {
  CustomClass customClass = CustomClass.newBuilder().build();
  FieldMask updateMask = FieldMask.newBuilder().build();
  CustomClass response = speechClient.updateCustomClassAsync(customClass, updateMask).get();
}
}</pre>

@param customClass Required. The CustomClass to update.
    <p>The CustomClass's `name` field is used to identify the CustomClass to update. Format:
    `projects/{project}/locations/{location}/customClasses/{custom_class}`.
@param updateMask The list of fields to be updated. If empty, all fields are considered for
    update.
@throws com.google.api.gax.rpc.ApiException if the remote call fails
java-speech/google-cloud-speech/src/main/java/com/google/cloud/speech/v2/SpeechClient.java