import java.util.ArrayList;
import java.util.List;

import org.slf4j.LoggerFactory;

public class Test1 { 
private static final Logger log = LoggerFactory.getLogger(Test1.class); 

private static class XX { 

} 
public static void main (String[] args) { 
List<XX> l = new ArrayList<>(); 
for (int i = 0; i < 5; ++i) { 
l.add(new XX()); 
} 
System.out.println(l.stream().reduce(0, (s, u) -> s + 1, (s1, s2) -> s1 + s2)); 
} 
}