Call a method at fixed time in Java

Question

How do I call a method at a particular time?

For example to call the method at 6:00 and 13:00.

I\'m working at a desktop application for Windows.

Answer 1

Have a look at the Timer and TimerTask classes. You can schedule a thread to execute at a specific time, or repeatedly.

public class Alarm {
    Timer _timer;

    public Alarm() {

        // Create a Date corresponding to 10:30:00 AM today.
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.HOUR_OF_DAY, 10);
        calendar.set(Calendar.MINUTE, 30);
        calendar.set(Calendar.SECOND, 0);

        Date alarmTime = calendar.getTime();

        _timer = new Timer();
        _timer.schedule(new AlarmTask(), alarmTime);
    }

    class AlarmTask extends TimerTask {
        /**
         * Called on a background thread by Timer
         */
        public void run() {
            // Do your work here; it's 10:30 AM!

            // If you don't want the alarm to go off again
            // tomorrow (etc), cancel the timer
            timer.cancel();
        }
    }
}

• Timer - http://java.sun.com/j2se/1.5.0/docs/api/java/util/Timer.html
• TimerTask - http://java.sun.com/j2se/1.4.2/docs/api/java/util/TimerTask.html