code: @Override
    @SuppressWarnings("unchecked")
    public <E> Comparator<E> getOrderBy() {
      return ObjectUtils.defaultIfNull(ComparatorHolder.get(), ObjectUtils.defaultIfNull(
        orderBy, ComparableComparator.INSTANCE));
    }
docs: Gets the Comparator used to order the elements in the collection.
  
  @param <E> the type of elements in the Collection to compare.
  @return the Comparator used to order the collection elements.
  @see java.util.Comparator