code: @Override
    public void onClose(Status status, Metadata trailers) {
      try (Scope scope = TRACER.withSpan(operationSpan)) {
        callWrapper.resetCall();
        rpcTimerContext.close();
        // OK
        if (status.isOk()) {
          if (onOK(trailers)) {
            finalizeStats(status);
          }
        } else {
          onError(status, trailers);
        }
      } catch (Exception e) {
        setException(e);
      }
    }
docs: {@inheritDoc}