GoogleCloudStorageReadChannel implements SeekableByteChannel { @VisibleForTesting long generation() { return resourceId.getGenerationId(); } GoogleCloudStorageReadChannel(
      Storage gcs,
      String bucketName,
      String objectName,
      ApiErrorExtractor errorExtractor,
      ClientRequestHelper<StorageObject> requestHelper);  GoogleCloudStorageReadChannel(
      Storage gcs,
      String bucketName,
      String objectName,
      ApiErrorExtractor errorExtractor,
      ClientRequestHelper<StorageObject> requestHelper,
      @Nonnull GoogleCloudStorageReadOptions readOptions);  GoogleCloudStorageReadChannel(
      Storage gcs,
      StorageResourceId resourceId,
      ApiErrorExtractor errorExtractor,
      ClientRequestHelper<StorageObject> requestHelper,
      @Nonnull GoogleCloudStorageReadOptions readOptions); protected  GoogleCloudStorageReadChannel(
      String bucketName, String objectName, @Nonnull GoogleCloudStorageReadOptions readOptions); void setMaxRetries(int maxRetries); @Override int read(ByteBuffer buffer); @Override SeekableByteChannel truncate(long size); @Override int write(ByteBuffer src); @Override boolean isOpen(); @Override void close(); @Override long position(); @Override SeekableByteChannel position(long newPosition); @Override long size();  }
@Test public void eagerReadFileAtSpecificGeneration_succeeds_whenReadConsistencyStrict() throws IOException { long generation = 5L; MockHttpTransport transport = mockTransport( jsonDataResponse(newStorageObject(BUCKET_NAME, OBJECT_NAME).setGeneration(generation))); List<HttpRequest> requests = new ArrayList<>(); Storage storage = new Storage(transport, JSON_FACTORY, requests::add); GoogleCloudStorageReadOptions options = GoogleCloudStorageReadOptions.builder().setFastFailOnNotFound(true).build(); GoogleCloudStorageReadChannel readChannel = createReadChannel(storage, options, generation); assertThat(readChannel.generation()).isEqualTo(generation); }