Java tutorial
import java.util.Arrays; import java.util.List; import java.util.function.Function; import java.util.function.Predicate; public class Main { public static void main(String[] args) { List<String> names = Arrays.asList("XML", "HTML", "Java", "Javascript", "CSS", "C"); Function<String, Predicate<String>> startsWithLetter = letter -> name -> name.startsWith(letter); names.stream().filter(startsWithLetter.apply("J")).forEach(System.out::println); } }