Java Stream - FILTER

package POMOS;

import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

public class StreamsPomos {
    public static void main(String[] args) {
        List<Integer> num=Arrays.asList(1,2,3,4,5);
        List<Integer> collect1=num.stream()
                .map(n->n *2)
                .collect(Collectors.toList());
        System.out.println(num);
        System.out.println(collect1);

        List<Integer> brojki=Arrays.asList(2,3,4,5);
        List<Integer> kvadrat=brojki.stream()
                .map(x->x*x)
                .collect(Collectors.toList());
        System.out.println(brojki);
        System.out.println(kvadrat);
    }
}