public static void waitAllEventsProcessed()
  {
    while (isEventThreadBusy())
    {
      readAndDispatchEvents();
    }
  }

  private static boolean isEventThreadBusy()
  {
    Thread thread = Thread.getAllStackTraces().keySet().stream()
        .filter(t -> t.getName().equals("EventAdmin Async Event Dispatcher Thread"))
        .findAny()
        .orElseThrow(() -> new IllegalStateException("Event Thread not found"));

    // if thread is not waiting, it is busy
    if (thread.getState() != State.WAITING)
    {
      return true;
    }

    // if thread's queue is not empty, it is busy
    Field headField;
    try
    {
      headField = thread.getClass().getDeclaredField("head");
      headField.setAccessible(true);
      if (headField.get(thread) != null)
      {
        return true;
      }
    }
    catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException e)
    {
      // fall through and ignore head field...
    }

    // if thread is not waiting for getNextEvent(), it is busy
    StackTraceElement[] stack = thread.getStackTrace();
    if (stack.length > 2)
    {
      StackTraceElement getNextEventExpected = stack[2];
      if (!getNextEventExpected.getMethodName().equals("getNextEvent"))
      {
        return true;
      }
    }

    // thread is really unoccupied
    return false;
  }