Java timer code execute JAR

Question

What is a good way, in terms of class libraries to use to achieve...

I want a java program to have a list of times [8.47am, 8.49am, 9pm..] and when each time is reached, run some code (that kicks off separate JAR). I can have a go but wanted some guidance as in the best classes to use for timer.. Maybe some are blocking/ non-blocking.

Thanks.

Answer 1

We can do this by using TimerTask class which implements runnable Interface internally. declare an arrayList and insert the desired time into it and the method call will be scheduled accordingly.

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;


//The task which you want to execute
class MyTimeTask extends TimerTask
{
    public void run()
    {
        System.out.println("DO some task");
    }

public static void main(String[] args) throws ParseException {

    //the Date and time at which you want to execute
    DateFormat dateFormatter = new SimpleDateFormat("yyyy-MM-dd HH:mm a");
    Date date = dateFormatter.parse("2018-05-23 12:43 am");
    Date date1 = dateFormatter.parse("2018-05-23 12:43 pm");
    ArrayList<Date> d=new ArrayList<>();
    d.add(date);
    d.add(date1);
    //Now create the time and schedule it
    Timer timer = new Timer();
    //Use this if you want to execute it once
   for(Date dd:d){
       timer.schedule(new MyTimeTask(),dd);
    }

    //Use this if you want to execute it repeatedly
    //int period = 10000;//10secs
    //timer.schedule(new MyTimeTask(), date, period );
 }
}