public Comparator<Hit> getComparator() {
        return null;
    }
Returns the Comparator that this HitOrderer uses internally to sort hits. Returns null if no Comparator is used.
<p>
This default implementation returns null.

@return the Comparator used to order hits, or null
container-search/src/main/java/com/yahoo/search/result/HitOrderer.java