import com.google.common.base.Optional; import java.util.ArrayList; import java.util.stream.Stream; public class Main { String m() { Stream<String> it = new ArrayList<String>().stream(); return java.util.Optional.ofNullable(it.map(s -> s + "asd").filter(s -> s.length() > 10).findFirst().orElseGet(Optional.fromNullable("10")::get)).orElse(null); } }