TimerTask is not working in Searcher in vespa

Question

I want to send notifications after every 30 seconds. I have scheduled my task using TimerTask but it is not working. Why is it so? My Searcher is given below:

@Override
public Result search(Query query, Execution execution) {

    // pass it down the chain to get a result
    Result result = execution.search(query);
    execution.fill(result);

    //the Date and time at which you want to execute
    DateFormat dateFormatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    Date date = null;
    try {
        date = dateFormatter.parse("2018-10-17 16:20:00");
    } catch (ParseException e) {
        e.printStackTrace();
    }

    //Now create the time and schedule it
    Timer timer = new Timer();

    assert date != null;
    timer.schedule(new TimerTask() {
        @Override
        public void run() {
            sendNotification();
        }
    }, date, 30000);


    // return the result up the chain
    return result;
}

Answer 1

The search() method is invoked on a per request basis and you are creating a new Timer instance per request which is garbage collected away by the Java VM some time after the search method returns as there are no references to it.