public static Collection<String> nodeId8s(@Nullable Collection<? extends ClusterNode> nodes){
  if (nodes == null || nodes.isEmpty())   return Collections.emptyList();
  return F.viewReadOnly(nodes,NODE2ID8);
}

public static Collection < String > nodeId8s ( @ Nullable Collection < ? extends ClusterNode > nodes ) { if ( nodes == null || nodes . isEmpty ( ) ) return Collections . emptyList ( ) ; return F . viewReadOnly ( nodes , NODE2ID8 ) ; }
convenient utility method that returns collection of node id8s for a given collection of grid nodes . id8 is a shorter string representation of node id , mainly the first 8 characters . < p > note that this method doesn ' t create a new collection but simply iterates over the input one .
