public class Test {

  public static boolean isPrime(int n) {
   .. as before
  }

  public static boolean isPrimeHappy(int n) {
    int total = 0;
    // calculate total of primes less than n
    for (int p = 2; p < n; p++) {
      if (isPrime(p)) {
        total += p;
      }
    }
    return (total % n == 0); // does n divide the total?

  }

  public static void main(String[] args) {
    System.out.println(isPrimeHappy(3));
    System.out.println(isPrimeHappy(5));
    System.out.println(isPrimeHappy(8));
  }
}