public static int compare(Object k1, Object k2) {
if (k1 == k2) return 0;
if (k1 != null) {
if (k2 == null) return 1;
if (k1 instanceof Number) return Numbers.compare((Number) k1, (Number) k2);
return ((Comparable) k1).compareTo(k2);
}
return -1;
}
