/**
* @return the type of the rule, either ATTRIBUTE or CLASS. All of the categories of
* a rule must be of one type or the other.
*/
public RuleTypeEnum getRuleType(){
RuleTypeEnum rc = RuleTypeEnum.CLASS;
for(RuleCategory cat: getRuleCategory()){
if (cat.getRuleType() == RuleTypeEnum.ATTRIBUTE){
rc = RuleTypeEnum.ATTRIBUTE;
break;
}