List<Integer> list = new ArrayList<>();
for (int i = 1; i<1001; i++){
    int sum = 0;
    for(int a=i; a>0; a/=10){
        sum += (a%10)*(a%10);
    }
    if (sum%2==0) list.add(i);
}

List<Integer> list = IntStream.range(1, 1000)
            .filter(number -> Math.sqrt(number) % 1 == 0)
            .boxed()
            .collect(Collectors.toList());

import java.util.ArrayList;
import java.util.List;
import java.util.stream.IntStream;

public class Lyambda {
    public static void main(String[] args) {
        List<Integer> list = new ArrayList<>();
        IntStream.range(0, 1000).forEach(
                i -> {
                    int sum = 0;
                    int number = i;
                    for(int j = 0; j < ("" + i).length(); j++) {
                        sum += (int) Math.pow(number%10, 2);
                        number = number/10;
                    }
                    if (sum%2 == 0)
//                      System.out.println("i = " + i + " sum = " + sum);
                        list.add(i);
                }
            );

        //Проверка
        for (Integer integer : list) {
            System.out.println(integer);
        }

    }

}