code: public boolean isUnacceptable(E element) {
  
      Ranking ranking = this.map.get(element);
      if (ranking == null) {
        return false;
      }
      return ranking.isUnacceptable();
    }
docs: This method determines if the given {@code element} has been {@link #setUnacceptable(Object) declared}
  {@link #RANK_UNACCEPTABLE unacceptable}.
  
  @param element is the element to check.
  @return {@code true} if the given {@code element} is unacceptable, {@code false} if the given element is
  acceptable.