像我们的朋友在评论区告诉你的那样做。它可能看起来像：

public static void main (String [] args) {
        List<Member> members = new ArrayList<>();
        members.add(new Member("Adam", "Gardening", LocalDate.parse("2020-01-06")));
        members.add(new Member("Paul", "Jogging", LocalDate.parse("2020-12-31")));
        members.add(new Member("Ben", "Yoga", LocalDate.parse("2020-12-05")));

        Collections.sort(members);
        System.out.println(members);
    }

    private static class Member implements Comparable<Member> {
        private String name;
        private String hobby;
        private LocalDate dateLogin;

        public Member(String name, String hobby, LocalDate dateLogin) {
            this.name = name;
            this.hobby = hobby;
            this.dateLogin = dateLogin;
        }

        @Override
        public int compareTo(Member member) {
            //from newest to olders
            return member.dateLogin.compareTo(dateLogin);

            //or from oldest to newest
            //dateLogin.compareTo(member.dateLogin);
        }

        @Override
        public String toString() {
            return "Member{" +
                    "name='" + name + '\'' +
                    ", hobby='" + hobby + '\'' +
                    ", dateLogin=" + dateLogin +
                    '}';
        }

        //getters and setters...

    }