return (getMaximum()+(getExtent()-1)-getMinimum()) / getExtent();
return ((getMaximum()+1)+(getExtent()-1)-getMinimum()) / getExtent();
    public final int getPageCount() {        // avoid division by zero        if ( getExtent()==0 )            return 0;        return (getMaximum()+(getExtent()-1)-getMinimum()) / getExtent();    }