code: @NullSafe
    public static <T extends Comparable<T>> Comparator<T> nullSafeComparator(Comparator<T> comparator) {
      return (comparator != null ? comparator : ComparatorUtils::compareIgnoreNull);
    }
docs: Null-safe check on the given {@link Comparator} returning the given {@link Comparator} if not {@literal null}
  or providing a default {@link Comparator }implementation if the given {@link Comparator} is {@literal null}.
  
  @param <T> {@link Comparable} class type of the objects in the comparison.
  @param comparator {@link Comparator} to evaluate for {@literal null}.
  @return the given {@link Comparator} if not {@literal null} or a default, provided {@link Comparator}
  implementation if the given {@link Comparator} is {@literal null}.
  @see #nullSafeArgumentsComparator(Comparator)
  @see java.util.Comparator