Question

How can I reschedule a timer. I have tried to cancel the timer/timertask and and schedule it again using a method. But its showing an exception error:

Exception errorjava.lang.IllegalStateException: TimerTask is scheduled already

Code I have used it :

private Timer timer = new Timer("alertTimer",true);
public void reScheduleTimer(int duration) {
    timer.cancel();
    timer.schedule(timerTask, 1000L, duration * 1000L);
}

Answer 1

If you see the documentation on Timer.cancel() you’ll see this:

“Cancels the Timer and all scheduled tasks. If there is a currently running task it is not affected. No more tasks may be scheduled on this Timer. Subsequent calls do nothing.”

You’ll need to initialize a new Timer when you are rescheduling:

EDIT:

public void reScheduleTimer(int duration) {
  timer = new Timer("alertTimer",true);
  timerTask = new MyTimerTask();
  timer.schedule(timerTask, 1000L, duration * 1000L);
}

private class MyTimerTask extends TimerTask {
  @Override
  public void run() {
    // Do stuff
  }
}