Find out the prime number

Here is the code program:

class Prime_number {
  public static void main(String[] args) {
    int num = 11;
    int i;
    for (i=2; i < num ;i++ ){
      int n = num%i;
      if (n==0){
        System.out.println("not Prime!");
        break;
      }
    }
    if(i == num){
      System.out.println("Prime number!");
    }
  }
}