code: @Override
    public void close() {
  
      LOG.log(Level.FINE, "EvaluatorIdlenessThreadPool shutdown: begin");
  
      this.executor.shutdown();
  
      boolean isTerminated = false;
      try {
        isTerminated = this.executor.awaitTermination(this.waitInMillis, TimeUnit.MILLISECONDS);
      } catch (final InterruptedException ex) {
        LOG.log(Level.WARNING, "EvaluatorIdlenessThreadPool shutdown: Interrupted", ex);
      }
  
      if (isTerminated) {
        LOG.log(Level.FINE, "EvaluatorIdlenessThreadPool shutdown: Terminated successfully");
      } else {
        final List<Runnable> pendingJobs = this.executor.shutdownNow();
        LOG.log(Level.SEVERE, "EvaluatorIdlenessThreadPool shutdown: {0} jobs after timeout", pendingJobs.size());
        LOG.log(Level.FINE, "EvaluatorIdlenessThreadPool shutdown: pending jobs: {0}", pendingJobs);
      }
    }
docs: Shutdown the thread pool of idleness checkers.