Printing out Prime Numbers from 2 to 1000

Question

I am writing a code that write all the prime numbers from 2 to 1000 in a file, named primes.txt. For some reason I am not able to figure out the correct way to do this probl

Answer 1

calculation can be made even faster by checking the division with prime numbers only. Any non prime number is divisible by some prime number smaller than itself.

    static List primes = new ArrayList();

public static void main(String[] args) {
    for (int i = 2; i < 10000; i++) {
        if(checkPrime(i)){
            primes.add(i);
        }
    }
    System.out.println(primes);
}

private static boolean checkPrime(int n) {
    for (Integer i : primes) {
        if(i*i > n ){
            break;
        }else if(n%i==0 )
            return false;
     }
    return true;
}