code: public static void resetOnLastOperator(String key) {
  		Objects.requireNonNull(key, "key");
  		log.debug("Reset onLastOperator: {}", key);
  
  		synchronized (log) {
  			onLastOperatorHooks.remove(key);
  			onLastOperatorHook = createOrUpdateOpHook(onLastOperatorHooks.values());
  		}
  	}
docs: Remove the sub-hook with key {@code key} from the onLastOperator hook. No-op if
  no such key has been registered, and equivalent to calling {@link #resetOnLastOperator()}
  if it was the last sub-hook.
  
  @param key the key of the sub-hook to remove