docs: public static List<String> getResourceIds(final CacheKey key) {
      try {
        final List<String> ids;
        if (key instanceof MultiCacheKey) {
          List<CacheKey> keys = ((MultiCacheKey) key).getCacheKeys();
          ids = new ArrayList<>(keys.size());
          for (int i = 0; i < keys.size(); i++) {
            ids.add(secureHashKey(keys.get(i)));
          }
        } else {
          ids = new ArrayList<>(1);
          ids.add(secureHashKey(key));
        }
        return ids;
      } catch (UnsupportedEncodingException e) {
        // This should never happen. All VMs support UTF-8
        throw new RuntimeException(e);
      }
    }