@Override
  public void setRowPositionSupplier(Supplier<Long> posSupplier) {
    if (reader instanceof SupportsRowPosition) {
      ((SupportsRowPosition) reader).setRowPositionSupplier(posSupplier);
    }
  }
A reader that produces Iceberg's internal in-memory object model.

<p>Iceberg's internal in-memory object model produces the types defined in {@link
Type.TypeID#javaClass()}.

@param <T> Java type returned by the reader
iceberg/patched-iceberg-core/src/main/java/org/apache/iceberg/avro/InternalReader.java