/**
* Sorts our values by {@code comparator} (and continually applies the comparator as new values
* are added/removed/set).
*/
public void setComparator(Comparator<E> comparator) {
this.persistentComparator = comparator;
List<E> copy = copyLastValue(getDirect());
if (copy != null && !copy.equals(getDirect())) {
set(copy);
}
}
