Не работает Comparator по нескольким полям

В FullComparator не работает сортировка по нескольким полям (channelName, DateCreated (в обратном порядке) и Fingerprint). Сортирует только по первому. Что делаю не так?

public class FullComparator implements Comparator<Capability> {
    @Override
    public int compare(Capability o1, Capability o2) {
        if (o1 != null && o2 != null) {
            if (o1.getChannelName() != null && o2.getChannelName() != null && !o1.getChannelName().equals(o2.getChannelName()))
                return o1.getChannelName().compareTo(o2.getChannelName());
            if (o1.getFingerprint() != null && o2.getFingerprint() != null && !o1.getFingerprint().equals(o2.getFingerprint()))
                return o1.getFingerprint().compareTo(o2.getFingerprint());
            if (o1.getDateCreated() != null && o2.getDateCreated() != null && !o2.getDateCreated().equals(o1.getDateCreated()))
                return o2.getDateCreated().compareTo(o1.getDateCreated());
        }
        if (o1 == null && o2 != null)
            return 1;
        if (o1 != null)
            return -1;
        return 0;
    }
}

public class Capability implements Comparable<Capability> {
    private long id;
    private String channelName;
    private String fingerprint;
    private boolean isActive;
    private Date dateCreated;
    public Capability(long id, String channelName, String fingerprint, boolean isActive, Date dateCreated) {
    this.id = id;
    this.channelName = channelName;
    this.fingerprint = fingerprint;
    this.isActive = isActive;
    this.dateCreated = dateCreated;
}
public long getId() {
    return id;
}
public String getChannelName() {
    return channelName;
}
public String getFingerprint() {
    return fingerprint;
}
public boolean isActive() {
    return isActive;
}
public Date getDateCreated() {
    return dateCreated;
}
@Override
public String toString() {
    return "Capability{" +
            "id=" + id +
            ", channelName='" + channelName + '\'' +
            ", fingerprint='" + fingerprint + '\'' +
            ", isActive=" + isActive +
            ", dateCreated=" + dateCreated +
            '}';
}

public class DemoComparator {
    public static void main(String[] args) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-mm-dd");
        Capability capability1 = new Capability(1001, "A", "R", true, sdf.parse("2015-12-15"));
        Capability capability2 = new Capability(1005, "D", "Z", false, sdf.parse("2010-12-15"));
        Capability capability3 = new Capability(900, null, "O", true, sdf.parse("2013-12-15"));
        Capability capability4 = new Capability(900, "B", "L", false, sdf.parse("2008-12-15"));
        ArrayList<Capability> capabilities = new ArrayList<>();
        capabilities.add(capability1);
        capabilities.add(capability2);
        capabilities.add(null);
        capabilities.add(capability4);
        System.out.println(capabilities);
        System.out.println();
        capabilities.sort(new FullComparator());
        System.out.println(capabilities);
    }
}

И разве метод может отсортировать все поля? Тогда получается нужно объектам полями меняться, чтобы одновременно в конечном результате все поля были в нужном порядке.