Printing Fibonacci Series

import java.util.*;
public class fibonacci
{
    static void main()
    {
    Scanner in = new Scanner(System.in);
    System.out.println("Enter the upper limit for the series ");
    int n = in.nextInt();
    int a = 0, b = 1;
    System.out.println("First " + n + " terms: ");
    for (int i = 1; i <= n; i++)
        {
            System.out.print(a + " , ");

            int sum = a + b;
            a = b;
            b = sum;
        }
    }
}