java - Adding Days to Calendar -

i'm new site , have started learning java. i'm trying add couple days gregoriancalendar doesn't work. here... (ignore top chunk), adding dates @ bottom annoying.

/*  * author:matt m  * date:8.12.13  * discription: when user inputs deadline, , difficulity of project,   * program gives date should start working on   */ import java.util.*; public class deadlineplanner{     public static void main(string[] args)     {         //take information , restart questions if information wrong          int month = 0, day = 0 ;                  {                 {         system.out.println("input month please");         month = (new scanner(system.in).nextint() - 1);         system.out.println("input day please");         day = (new scanner(system.in).nextint());          }         while (!(month <= 12) || !(month >= 0));         }        while (!(day <= 31) || !(month >= 0));         //make new calender , initialize         gregoriancalendar setup = new gregoriancalendar();        setup.set(2013, month, day);        system.out.println("the deadline "+ setup.gettime());         //switch statement give starting date        system.out.println("is project hard or easy?");        scanner difficulity = new scanner(system.in);         switch (difficulity.nextline())        {             case "easy":                  setup.add(day, -1);                system.out.print("the date should start workinng on ");                system.out.println(setup.gettime());                break;            case "hard":                 setup.add(day, -10);                system.out.print("the date should start workinng on ");                system.out.println(setup.gettime());                 break;            default:                system.out.println("your answers questions incorrect");                break;        }      } } 

thanks reading through this!i'm open feedback...

there's code here. user interaction.

start simple method 1 thing, work way out after right.

here's how might it:

public class dateutils {     private dateutils() {}      public static date adddays(date basedate, int daystoadd) {         calendar calendar = calendar.getinstance();         calendar.settime(basedate);         calendar.add(calendar.day_of_year, daystoadd);         return calendar.gettime();     } } 

once have method tested , proven can let rest of code call it.

update: it's 4 years later, , jdk 8 has given new joda-based time package. should using classes, not jdk 1.0 calendar.