code: protected void nullReference( List<Comparison> comparisons,
                                    Iterable<Comparison> comparisonsToNull ) {
          for (Comparison comparisonToNull : comparisonsToNull) {
              nullReference(comparisons, comparisonToNull);
          }
      }
docs: Find all references in the supplied list that match those supplied and set them to null.
  
  @param comparisons the collection in which null references are to be placed
  @param comparisonsToNull the comparisons that are to be found and nulled in the collection