code: public <RowT> UnaryCallable<Query, RowT> createReadRowCallable(RowAdapter<RowT> rowAdapter) {
      return createReadRowsCallable(
              ServerStreamingCallSettings.<Query, Row>newBuilder()
                  .setRetryableCodes(settings.readRowSettings().getRetryableCodes())
                  .setRetrySettings(settings.readRowSettings().getRetrySettings())
                  .setIdleTimeout(settings.readRowSettings().getRetrySettings().getTotalTimeout())
                  .build(),
              rowAdapter)
          .first();
    }
docs: Creates a callable chain to handle point ReadRows RPCs. The chain will:
  
  <ul>
  <li>Convert a {@link Query} into a {@link com.google.bigtable.v2.ReadRowsRequest} and
  dispatch the RPC.
  <li>Upon receiving the response stream, it will merge the {@link
  com.google.bigtable.v2.ReadRowsResponse.CellChunk}s in logical rows. The actual row
  implementation can be configured in by the {@code rowAdapter} parameter.
  <li>Retry/resume on failure.
  <li>Filter out marker rows.
  </ul>