长时间运行的操作 (LRO)

对 Google Ads API 的多次调用都会返回长时间运行的操作 (LRO)。这些对象会跟踪长时间执行的作业的状态，而无需单个阻塞 RPC。

OperationFuture 类

在 Java 客户端库中，您可以使用 OperationFuture 类与 LRO 进行交互。由于 OperationFuture 依赖于底层服务客户端来轮询 API 以获取状态更新，因此请确保服务客户端在操作完成之前保持打开和活跃状态。

不推荐：

private void executeOperation(String jobName) throws Exception {
  OperationFuture<Empty, OfflineUserDataJobMetadata> future =
      startLongRunningOperation(jobName);
  // FAILS: The service client was already closed when
  // startLongRunningOperation() exited its try-with-resources block, so
  // future.get() fails when polling.
  future.get();
}

private OperationFuture<Empty, OfflineUserDataJobMetadata>
    startLongRunningOperation(String jobToStart) {
  try (OfflineUserDataJobServiceClient offlineUserDataJobServiceClient =
      googleAdsClient
          .getLatestVersion()
          .createOfflineUserDataJobServiceClient()) {
    // Issues an asynchronous request to run the offline user data job.
    return offlineUserDataJobServiceClient.runOfflineUserDataJobAsync(
        jobToStart);
  }
}

推荐：

private void executeOperation(String jobName) throws Exception {
  try (OfflineUserDataJobServiceClient offlineUserDataJobServiceClient =
      googleAdsClient
          .getLatestVersion()
          .createOfflineUserDataJobServiceClient()) {
    OperationFuture<Empty, OfflineUserDataJobMetadata> future =
        startLongRunningOperation(offlineUserDataJobServiceClient, jobName);
    // Waits for the operation to complete (with a timeout) while the client is
    // still open.
    future.get(5, TimeUnit.MINUTES);
  }
}

private OperationFuture<Empty, OfflineUserDataJobMetadata>
    startLongRunningOperation(
        OfflineUserDataJobServiceClient offlineUserDataJobServiceClient,
        String jobToStart) {
  return offlineUserDataJobServiceClient.runOfflineUserDataJobAsync(jobToStart);
}

请注意，OperationFuture 仅在 OfflineUserDataJobServiceClient 在 try-with-resources 块中保持打开状态时使用。