Java Code Examples for com.google.android.gms.tasks.Task#continueWithTask()

/**
 * List all items (files) and prefixes (folders) under this StorageReference.
 *
 * <p>This is a helper method for calling {@code list()} repeatedly until there are no more
 * results. Consistency of the result is not guaranteed if objects are inserted or removed while
 * this operation is executing.
 *
 * <p>{@code listAll()} is only available for projects using <a
 * href="https://firebase.google.com/docs/rules/rules-behavior#security_rules_version_2">Firebase
 * Rules Version 2</a>.
 *
 * @throws OutOfMemoryError If there are too many items at this location.
 * @return A {@link Task} that returns all items and prefixes under the current StorageReference.
 */
@NonNull
public Task<ListResult> listAll() {
  TaskCompletionSource<ListResult> pendingResult = new TaskCompletionSource<>();

  List<StorageReference> prefixes = new ArrayList<>();
  List<StorageReference> items = new ArrayList<>();

  Executor executor = StorageTaskScheduler.getInstance().getCommandPoolExecutor();
  Task<ListResult> list = listHelper(/* maxResults= */ null, /* pageToken= */ null);

  Continuation<ListResult, Task<Void>> continuation =
      new Continuation<ListResult, Task<Void>>() {
        @Override
        public Task<Void> then(@NonNull Task<ListResult> currentPage) {
          if (currentPage.isSuccessful()) {
            ListResult result = currentPage.getResult();
            prefixes.addAll(result.getPrefixes());
            items.addAll(result.getItems());

            if (result.getPageToken() != null) {
              Task<ListResult> nextPage =
                  listHelper(/* maxResults= */ null, result.getPageToken());
              nextPage.continueWithTask(executor, this);
            } else {
              pendingResult.setResult(new ListResult(prefixes, items, /* pageToken= */ null));
            }
          } else {
            pendingResult.setException(currentPage.getException());
          }

          return Tasks.forResult(null);
        }
      };

  list.continueWithTask(executor, continuation);

  return pendingResult.getTask();
}
 

@Override
public synchronized Task<String> getToken() {
  boolean doForceRefresh = forceRefresh;
  forceRefresh = false;
  Task<GetTokenResult> res = authProvider.getAccessToken(doForceRefresh);

  // Take note of the current value of the tokenCounter so that this method can fail (with a
  // FirebaseFirestoreException) if there is a token change while the request is outstanding.
  final int savedCounter = tokenCounter;
  return res.continueWithTask(
      Executors.DIRECT_EXECUTOR,
      task -> {
        synchronized (this) {
          // Cancel the request since the token changed while the request was outstanding so the
          // response is potentially for a previous user (which user, we can't be sure).
          if (savedCounter != tokenCounter) {
            Logger.debug(LOG_TAG, "getToken aborted due to token change");
            return getToken();
          }

          if (task.isSuccessful()) {
            return Tasks.forResult(task.getResult().getToken());
          } else {
            return Tasks.forException(task.getException());
          }
        }
      });
}
 

private <T> Task<Void> updateUiAfterTask(Task<T> task) {
    Task<Void> loadFolderTask = task.continueWithTask(task1 -> {
        DriveFolder currentFolder = mNavigationPath.peek().asDriveFolder();
        return loadFolderNameAndContents(currentFolder);
    });
    // Wait till Metadata is loaded to allow user interaction.
    loadFolderTask.addOnCompleteListener(task12 -> setUiInteractionsEnabled(true));
    return loadFolderTask;
}
 

/**
 * Fetches from the backend if the fetched configs cache has expired and the client is not
 * currently throttled.
 *
 * <p>If a fetch request is made to the backend, updates the last fetch status, last successful
 * fetch time and {@link BackoffMetadata} in {@link ConfigMetadataClient}.
 */
private Task<FetchResponse> fetchIfCacheExpiredAndNotThrottled(
    Task<ConfigContainer> cachedFetchConfigsTask, long minimumFetchIntervalInSeconds) {
  Date currentTime = new Date(clock.currentTimeMillis());
  if (cachedFetchConfigsTask.isSuccessful()
      && areCachedFetchConfigsValid(minimumFetchIntervalInSeconds, currentTime)) {
    // Keep the cached fetch values if the cache has not expired yet.
    return Tasks.forResult(FetchResponse.forLocalStorageUsed(currentTime));
  }

  Task<FetchResponse> fetchResponseTask;

  Date backoffEndTime = getBackoffEndTimeInMillis(currentTime);
  if (backoffEndTime != null) {
    // TODO(issues/260): Provide a way for users to check for throttled status so exceptions
    // aren't the only way for users to determine if they're throttled.
    fetchResponseTask =
        Tasks.forException(
            new FirebaseRemoteConfigFetchThrottledException(
                createThrottledMessage(backoffEndTime.getTime() - currentTime.getTime()),
                backoffEndTime.getTime()));
  } else {
    Task<String> installationIdTask = firebaseInstallations.getId();
    Task<InstallationTokenResult> installationAuthTokenTask =
        firebaseInstallations.getToken(false);
    fetchResponseTask =
        Tasks.whenAllComplete(installationIdTask, installationAuthTokenTask)
            .continueWithTask(
                executor,
                (completedInstallationsTasks) -> {
                  if (!installationIdTask.isSuccessful()) {
                    return Tasks.forException(
                        new FirebaseRemoteConfigClientException(
                            "Firebase Installations failed to get installation ID for fetch.",
                            installationIdTask.getException()));
                  }

                  if (!installationAuthTokenTask.isSuccessful()) {
                    return Tasks.forException(
                        new FirebaseRemoteConfigClientException(
                            "Firebase Installations failed to get installation auth token for fetch.",
                            installationAuthTokenTask.getException()));
                  }

                  String installationId = installationIdTask.getResult();
                  String installationToken = installationAuthTokenTask.getResult().getToken();
                  return fetchFromBackendAndCacheResponse(
                      installationId, installationToken, currentTime);
                });
  }

  return fetchResponseTask.continueWithTask(
      executor,
      (completedFetchTask) -> {
        updateLastFetchStatusAndTime(completedFetchTask, currentTime);
        return completedFetchTask;
      });
}