code: public static <T> List<Callback<? super T>> dispatchSuccessClear(
      List<Callback<? super T>> list, T result) {
      if (list != null) {
        for (int ii = 0, ll = list.size(); ii < ll; ii++)
          list.get(ii).onSuccess(result);
      }
      return null;
    }
  
    /**
     * Dispatches {@link Callback#onSuccess} to all callbacks in {@code list} using {@code result}.
     * If {@code list} is null, does nothing. Returns {@code null} to support standard usage pattern.
     */
    public static <T> List<Callback<? super T>> dispatchFailureClear(
      List<Callback<? super T>> list, Throwable cause) {
      if (list != null) {
        for (int ii = 0, ll = list.size(); ii < ll; ii++)
          list.get(ii).onFailure(cause);
      }
      return null;
    }
  }
docs: Dispatches {@link Callback#onSuccess} to all callbacks in {@code list} using {@code result}.
  If {@code list} is null, does nothing. Returns {@code null} to support standard usage pattern.