code: public boolean add(String inputValue) {
          String value = Normalizer.normalize(inputValue, Normalizer.NORMALIZE_LOWER);
          if (!contains(this.genericValues, value)) {
              addElement(value);
              return true;
          }
          return false;
      }
docs: Add the generic value to this handler with no required key.
  
  @param inputValue
  @return boolean (true means success adding)