Twin Prime Number

Twin Prime Numbers are numbers who have a difference of two and both of the numbers are Prime Numbers.

Example 1: 3 and 5. 5-3 = 2. Also 3 and 5 both are Prime Numbers. Hence they are Twin Prime Numbers.

Example 2: 3 and 7. 7-3 = 4. Here though 3 and 7 both are Prime Numbers their difference is not two. Hence they are not Twin Prime Numbers.

Java
import java.util.*;
public class TwinPrimeNumber
{
    public static void main(String args[])
    {
        int n1=0,n2=0,flag=0;
        Scanner sc=new Scanner(System.in);
        System.out.println("Enter two numbers:-");
        n1=sc.nextInt();
        n2=sc.nextInt();
        if(Math.abs(n1-n2)==2)
        {
            for(int i=1;i<=n1;i++)
            {
                if(n1%i==0)
                {
                    flag++;
                }
            }
            if(flag==2)
            {
                flag=0;
                for(int i=1;i<=n2;i++)
                {
                    if(n2%i==0)
                    {
                        flag++;
                    }
                }
                if(flag==2)
                {
                    System.out.println(n1+" and "+n2+" are Twin Prime Numbers");
                }
            }
        }
        if(flag!=2)
        {
            System.out.println(n1+" and "+n2+" are not Twin Prime Numbers");
        }
    }
}
Java