import com.google.common.base.Optional; import com.google.common.collect.FluentIterable; import java.util.ArrayList; public class Main { String m() { FluentIterable<String> i<caret>t = FluentIterable.from(new ArrayList<>()); return it.transform(s -> s + "asd").firstMatch(s -> s.length() > 10).or(Optional.fromNullable("10")).orNull(); } }