Java Month Day date plus minus

 Public Static String date_year= "Year"; // years  Public Static String date_month= "MONTH"; // Month  Public Static String date_day= "Day"; // Day

// 7 Days Date date_day = dateoperation (date_day,-7); // 1 months Date date_month = dateoperation (date_month,-1); // 1 Years Date date_year = dateoperation (date_year,-1);

    PrivateDate dateoperation (String dateoperationtype,integer amount)throwsException {Calendar cal=calendar.getinstance (); SimpleDateFormat SDF=NewSimpleDateFormat ("Yyyy-mm-dd"); String s= Sdf.format (NewDate ()); Date Today=Sdf.parse (s);        Cal.settime (today); if(Date_day.equals (Dateoperationtype)) {Cal.add (cal.        Day_of_month,amount); }        if(Date_month.equals (Dateoperationtype)) {Cal.add (cal.        Month,amount); }        if(Date_year.equals (Dateoperationtype)) {Cal.add (cal.        Year,amount); }//System.out.println (Cal.gettime ());        returnCal.gettime (); }

Java Month Day date plus minus