Comment trier une liste d'objets par plusieurs propriétés en Java ?

public class ActiveAlarm {
    public long timeStarted;
    public long timeEnded;
    // ... other fields
}

List<ActiveAlarm> alarms = ...;

Comparator<ActiveAlarm> comparator =
    Comparator.comparing(alarm -> alarm.timeStarted)
              .thenComparing(alarm -> alarm.timeEnded);

Collections.sort(alarms, comparator);

Comparator<ActiveAlarm> comparator =
    (alarm1, alarm2) -> {
        int result = Long.compare(alarm1.timeStarted, alarm2.timeStarted);
        if (result == 0) {
            result = Long.compare(alarm1.timeEnded, alarm2.timeEnded);
        }
        return result;
    };

Comparator<ActiveAlarm> comparator = new Comparator<ActiveAlarm>() {
    @Override
    public int compare(ActiveAlarm o1, ActiveAlarm o2) {
        int result = Long.compare(o1.timeStarted, o2.timeStarted);
        if (result == 0) {
            result = Long.compare(o1.timeEnded, o2.timeEnded);
        }
        return result;
    }
};