return s1.compareTo(s2);
return s1==null ? (s2==null ? 0 : -1)  : s1.compareTo(s2);
    public final static int compare(Collator collator, String s1, String s2) {        if (collator == null)            return s1.compareTo(s2);        else            return collator.compare(s1, s2);    }