JAVA Help

import java.util.*;
class convert
{
    int n,d,m,y;
    convert()
    {
        n=0;
        d=0;
        m=0;
        y=0;
    }
    void accept()
    {
        Scanner s=new Scanner(System.in);
        System.out.println("Enter day number");
        n=s.nextInt();
        System.out.println("Enter year");
        y=s.nextInt();
    }
    void day_to_date()
    {
        int arr[]={0,31,28,31,30,31,30,31,31,30,31,30,31};
        int i,sum=0;
        if (y%4==0)
        arr[2]=29;
        for (i=1;i<=12;i++)
        {
            sum=sum+arr[i];
            if (sum>=n)
            break;
        }
        d=arr[i]-(sum-n);
        m=i;
    }
    void display()
    {
        String str[]={"","Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"};
        System.out.println(str[m]+" "+d+","+y);
    }
    public static void main()
    {
        convert obj=new convert();
        obj.accept();
        obj.day_to_date();
        obj.display();
    }
}