Java Stream How to - Map to double the value

Question

We would like to know how to map to double the value.

Answer

import java.util.Arrays;
import java.util.List;
//from   www  .  j  av  a 2 s . c  om
public class Main {
   public static void main(String[] args) {
     List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5);
     numbers.stream().map(n -> n * n).forEach(System.out::println);
   }

}

The code above generates the following result.