private boolean updateComparators(Comparator choicesComparator,
                                      Comparator<String> stringComparator) {
        boolean same = this.strComparator.equals(stringComparator);
        if (same){
        	if (choicesComparator==null){
        		same = this.contentComparator==null;
        	} else {
        		same = choicesComparator.equals(this.contentComparator);
        	}
        }
        this.contentComparator = choicesComparator;
        this.strComparator = stringComparator;
        return !same;
    }
private boolean updateComparators(Comparator choicesComparator,
                                      Comparator<String> stringComparator)