@GetInitialRestriction
  public OffsetByteRange getInitialRestriction(
      @Element SubscriptionPartition subscriptionPartition) {
    Offset offset = offsetReaderFactory.apply(subscriptionPartition).read();
    return OffsetByteRange.of(new OffsetRange(offset.value(), Long.MAX_VALUE /* open interval */));
  }
@Test
  public void getInitialRestrictionReadFailure() {
    when(initialOffsetReader.read()).thenThrow(new CheckedApiException(Code.INTERNAL).underlying);
    assertThrows(ApiException.class, () -> sdf.getInitialRestriction(PARTITION));
  }