code: @Override
    public void close() {
  
      LOG.log(Level.FINER, "Closing the evaluators - begin");
  
      final List<EvaluatorManager> evaluatorsCopy;
      synchronized (this) {
        evaluatorsCopy = new ArrayList<>(this.evaluators.values());
      }
  
      for (final EvaluatorManager evaluatorManager : evaluatorsCopy) {
        if (!evaluatorManager.isClosedOrClosing()) {
          LOG.log(Level.WARNING, "Unclean shutdown of evaluator {0}", evaluatorManager.getId());
          evaluatorManager.close();
        }
      }
  
      LOG.log(Level.FINER, "Closing the evaluators - end");
    }
docs: Closes all EvaluatorManager instances managed.