public int getHeadRulePriority(String category, String edgeLabel, String childCategory) {
			if (!headRules.containsKey(category) || !headRules.get(category).containsKey(edgeLabel))
				return Integer.MAX_VALUE;
			if (headRules.get(category).get(edgeLabel).containsKey(""))
				return headRules.get(category).get(edgeLabel).get("");
			if (headRules.get(category).get(edgeLabel).containsKey(childCategory))
				return headRules.get(category).get(edgeLabel).get(childCategory);
			return Integer.MAX_VALUE;
		}