1import java.util.Map;
2import java.util.concurrent.ConcurrentHashMap;
3
4public class Test {
5 public static void main(String[] s) {
6 Map<String, Boolean> whoLetDogsOut = new ConcurrentHashMap<>();
7 whoLetDogsOut.computeIfAbsent("snoop", k -> f(k));
8 whoLetDogsOut.computeIfAbsent("snoop", k -> f(k));
9 }
10 static boolean f(String s) {
11 System.out.println("creating a value for \""+s+'"');
12 return s.isEmpty();
13 }
14}