I have this java program which calculates the time that the person took to respond to the confirm dialog box. But it seems that both time1 and time 2 gets the same value. What have I done wrong here:

import javax.swing.JOptionPane;
    import java.util.*;

    public class DialogTimer{
        public static void main(String args[]){
            int time1, time2, milli1, milli2, sec1, sec2, timeDifference;
            final int MILLISECSINSECOND =1000;

            JOptionPane.showConfirmDialog(null, "Is stealing ever justified? ");

            GregorianCalendar before=new GregorianCalendar();
                GregorianCalendar after= new GregorianCalendar();


            milli1=before.get(GregorianCalendar.MILLISECOND);
            milli2=after.get(GregorianCalendar.MILLISECOND);


            sec1=before.get(GregorianCalendar.SECOND);
            sec2=after.get(GregorianCalendar.SECOND);

            time1=MILLISECSINSECOND * sec1 + milli1;
            time2=MILLISECSINSECOND * sec2 + milli2;


            //timeDifference=time1 - time2;
            System.out.println(time1);
            System.out.println(time2);


            //JOptionPane.showMessageDialog(null, "It took " + (time1 - time2) + " milliseconds for you to answer");


        }

    }