/** merges a Reflections instance metadata into this instance */
 public Reflections merge(final Reflections reflections) {
   if (reflections.store != null) {
     for (String indexName : reflections.store.keySet()) {
       Multimap<String, String> index = reflections.store.get(indexName);
       for (String key : index.keySet()) {
         for (String string : index.get(key)) {
           store.getOrCreate(indexName).put(key, string);
         }
       }
     }
   }
   return this;
 }