docs: public void rebuild(StaplerRequest req, JSONObject json, List<? extends Descriptor<T>> descriptors) throws FormException, IOException {
          List<T> newList = new ArrayList<>();
  
          for (Descriptor<T> d : descriptors) {
              T existing = get((D)d);
              String name = d.getJsonSafeClassName();
              JSONObject o = json.optJSONObject(name);
  
              T instance = null;
              if (o!=null) {
                  if (existing instanceof ReconfigurableDescribable)
                      instance = (T)((ReconfigurableDescribable)existing).reconfigure(req,o);
                  else
                      instance = d.newInstance(req, o);
              } else {
                  if (existing instanceof ReconfigurableDescribable)
                      instance = (T)((ReconfigurableDescribable)existing).reconfigure(req,null);
              }
  
              if (instance!=null)
                  newList.add(instance);
          }
  
          replaceBy(newList);
      }