code: @SuppressWarnings("unchecked")
    public <C extends CDACallback<CDAArray>> C all(C callback) {
      return (C) Callbacks.subscribeAsync(baseQuery().all(), callback, client);
    }
docs: Async fetch all resources matching the type of this query.
  
  @param callback callback.
  @param <C>      callback type.
  @return the given {@code callback} instance.