@Test
public void testSampleRowKeysAsync() throws Exception {

  List<KeyOffset> expectedKeyOff =
      ImmutableList.of(KeyOffset.create(ByteString.copyFromUtf8(ROW_KEY), 10));
  when(dataClientV2.sampleRowKeysAsync(TABLE_ID)).thenReturn(immediateFuture(expectedKeyOff));
  List<KeyOffset> keyOffSets = dataGCJClient.sampleRowKeysAsync(TABLE_ID).get();
  assertEquals(expectedKeyOff, keyOffSets);
  verify(dataClientV2).sampleRowKeysAsync(TABLE_ID);
}