isPrime java

static boolean isPrime(int n) { 
        // Base cases 
        if (n <= 1) 
            return false; 
        if (n <= 3) 
            return true; 
        // This is checked so that we can skip 
        // middle five numbers in below loop 
        if (n % 2 == 0 || n % 3 == 0) 
            return false; 
  		// only check cases in Form 6k ± 1
        for (int i = 5; i * i <= n; i = i + 6) 
            if (n % i == 0 || n % (i + 2) == 0) 
                return false; 
  
        return true; 
}