code: public Map<String, Process> getRuleFlows() {
          ProcessPackage rtp = (ProcessPackage) getResourceTypePackages().get(ResourceType.BPMN2);
          return rtp == null? Collections.emptyMap() : rtp.getRuleFlows();
      }
docs: Get the rule flows for this package. The key is the ruleflow id. It will
  be Collections.EMPTY_MAP if none have been added.