docs: @Override
      public boolean isThreadSafe(Tuple<ScriptEngine, String> key, ScriptEvaluator instance) {
          final ScriptEngineFactory factory = key.first.getFactory();
          final Object threadingAbility = factory.getParameter("THREADING");
          return threadingAbility != null && ("THREAD-ISOLATED".equals(threadingAbility) || "STATELESS".equals(threadingAbility));
      }