code: public MatchRule getMatchRule(int index) {
  		if (index < rules.size()) {
  			return rules.get(index);
  		}
  		return null;
  	}
docs: Get an existing match rule of the scan.
  
  If no match rule exists at the specified index, this method returns null.
  
  @param index Index of the match rule to return
  @return The match rule at the specified index, or null if none exists