Prime numbers with Java8 Stream API

Main.java

import java.util.stream.IntStream;

class Main {
    public static void main(String args[]) {
        IntStream.rangeClosed(2, 100)
            .filter(i -> IntStream.rangeClosed(2, (int)Math.sqrt(i))
                    .allMatch(j -> i%j != 0))
            .forEach(n -> {
                System.out.println(n);
            });
    }
}

Hi,

Quite inefficient, please refer to Miller-Rabin or Lehman test for checking the primality of a number.

// check if number return true when it divided by it self and one only
IntPredicate isDivisible = index -> number % index == 0;
// test the number
isDivisible.test(number);
// check if numbers between 2 and the provided number is prime
return IntStream.range(2, number - 1).noneMatch(isDivisible);