Write a program of prime number

import java.io.*;

class Prime

{

          public static void main(String[] arg)

          throws IOException

          {

                   int i=2;

                   BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

                   System.out.println("enter the first number");

                   int n=Integer.parseInt(br.readLine());

                   for(i=2;i<=n/2;i++)

                   {

                             if(n%i==0)

                             break;

                   }

                   if(i==((n/2)+1))

                   System.out.println("prime");

                   else

                   System.out.println("not prime");

          }

}