docs: private N createRoot(N root, List<E> objects) {
      // insert data
      for(E entry : objects) {
        if (entry instanceof LeafEntry) {
          root.addLeafEntry(entry);
        }
        else {
          root.addDirectoryEntry(entry);
        }
      }
  
      // set root mbr
      ((SpatialDirectoryEntry) getRootEntry()).setMBR(root.computeMBR());
  
      // write to file
      writeNode(root);
      if(getLogger().isDebuggingFiner()) {
        StringBuilder msg = new StringBuilder();
        msg.append("pageNo ").append(root.getPageID());
        getLogger().debugFiner(msg.toString());
      }
  
      return root;
    }