public static void main(String[] args) throws ParseException {
List<Student> list = new ArrayList<>();
list.add(new Student("zhangsan",10,TimeUtils.stringToDate("2022-07-07 22:20:41")));
list.add(new Student("zhangsan",30,TimeUtils.stringToDate("2022-07-07 22:20:43")));
list.add(new Student("zhangsan",20,TimeUtils.stringToDate("2022-07-07 22:20:42")));
list.add(new Student("zhangsan",40,TimeUtils.stringToDate("2022-07-07 22:20:46")));
list.add(new Student("lisi",30,TimeUtils.stringToDate("2022-07-07 22:20:43")));
Map<String, List<Student>> map = list.stream().collect(Collectors.groupingBy(Student::getName));
map.keySet().forEach(key -> {
List<Student> students = map.get(key);
List<Date> dateList = students.stream().map(Student::getBirth).collect(Collectors.toList());
Date date = dateList.stream().max(Date::compareTo).get();
List<Student> maxAgeStu = students.stream().filter(s -> s.getBirth().getTime() == date.getTime()).collect(Collectors.toList());
System.out.println(maxAgeStu);
});