public ErrorStatsData getStats(String route, String cause) {
        Map<String, ErrorStatsData> map = routeMap.get(route);
        if (map == null) {
            return null;
        }
        return map.get(cause);
    }
@param route
@param cause
@return data structure for holding count information for a route and cause
zuul-core/src/main/java/com/netflix/zuul/stats/ErrorStatsManager.java