public static IndexReader maybeWrapReader(IndexReader r) throws IOException {
  if (rarely()) {
    r=wrapReader(r);
  }
  return r;
}

public static IndexReader maybeWrapReader ( IndexReader r ) throws IOException { if ( rarely ( ) ) { r = wrapReader ( r ) ; } return r ; }
sometimes wrap the indexreader as slow , parallel or filter reader ( or combinations of that )
