Count int occurrences with Java8

Question

Is there a better way to count int occurrences with Java8

int[] monthCounter = new int[12];
persons.stream().forEach(person -> monthCounter[person.getBirt         


        

Answer 1

Already answered. Small Suggestion from my side inorder to eliminate null pointer exception ie From the stream null will throw java.lang.UnsupportedOperationException, java.lang.NullPointerException

Map birthdayCount = persons.stream()
                                    .filter(Objects::nonNull) // filter out null object
                                    .filter(p->Objects.nonNull(p.getBirthday())) // filter out null birthdays
                                    .collect(Collectors.groupingBy(p -> 
                                                 p.getBirthday().getMonthValue(), 
                                                 Collectors.counting()));