Date and Time --- Simple Arithmetic

/* Program to add and subtract days and Hours. It can be applied for other fields of date and time too */

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package test;
import java.util.Calendar;


public class DateTimeUtility {
    public static void main(String[] args) {
        int addDays = 4;
        int subtractDays = 10;
        int addHours=3;
        int subtractHours=26;
     
        Calendar cal = Calendar.getInstance();
        //System.out.println(cal);
        //Current date
        System.out.println("Today's date : " + (cal.get(Calendar.MONTH) + 1) +
                "/" + cal.get(Calendar.DATE) + "/" + cal.get(Calendar.YEAR));
   
        //Current Time
        System.out.println("Current Time  : " + (cal.get(Calendar.HOUR) ) +
                ":" + cal.get(Calendar.MINUTE) + ":" + cal.get(Calendar.SECOND));

        //Adding days
        cal.add(Calendar.DATE, addDays);
        System.out.println("Date (after): " + (cal.get(Calendar.MONTH) + 1) +
                "/" + cal.get(Calendar.DATE) + "/" + cal.get(Calendar.YEAR));
        cal = Calendar.getInstance();

        //subtracting days
        cal.add(Calendar.DATE, -subtractDays);
        System.out.println("Date (before): " + (cal.get(Calendar.MONTH) + 1) +
               "/" + cal.get(Calendar.DATE) + "/" + cal.get(Calendar.YEAR));

       //Adding Hours
        cal.add(Calendar.HOUR, addHours);
        System.out.println("New Time after adding " + addHours +" Hours "+
                cal.get(Calendar.HOUR) + ":" + cal.get(Calendar.MINUTE) +
                ":" + cal.get(Calendar.SECOND));
        cal=Calendar.getInstance();

       //Subtracting Hours
        cal.add(Calendar.HOUR, -subtractHours);
        System.out.println("Time before " + subtractHours+" Hours "+
                (cal.get(Calendar.HOUR) ) + ":" + cal.get(Calendar.MINUTE) +
                ":" + cal.get(Calendar.SECOND));
    }
}

OUTPUT :

Today's date : 2/22/2014
Current Time  : 6:22:6
Date (after): 2/26/2014
Date (before): 2/12/2014
New Time after adding 3 Hours 9:22:6
Time before 26 Hours 4:22:6