@Override
    @Nullable public ZuulFilter<?, ?> getFilterByNameAndType(String name, FilterType type) {
        Map<String, ZuulFilter<?, ?>> filtersByName = filtersByTypeAndName.get(type);
        if (filtersByName == null) {
            return null;
        }
        return filtersByName.get(name);
    }
An immutable static collection of filters.
zuul-core/src/main/java/com/netflix/zuul/StaticFilterLoader.java