* to call getCopy and removeAllNodes only with a true K, then we could check containsKey first.
     * But that check wouldn't eliminate the warnings.)
     */
    @SuppressWarnings({"unchecked", "nullness"})
    K castKey = (K) key;
    List<V> oldValues = getCopy(castKey);
    removeAllNodes(castKey);
    return oldValues;
  }

  @Override

            final String schedulerId = getSchedulerIds(namePrefix).get(0);
            final Response response = checkMethodBase(requestBody).post("/api/admin/scheduler/" + schedulerId + "/start");
            if (response.getBody().jsonPath().getInt("response.status") == 0) {
                logger.info("Start scheduler \"{}\"", schedulerId);
                return;
            }
            ThreadUtil.sleep(1000L);
        }