docs: public synchronized void register(String id, MapInterceptor interceptor) {
          assert !(Thread.currentThread() instanceof PartitionOperationThread);
  
          if (id2InterceptorMap.containsKey(id)) {
              return;
          }
  
          Map<String, MapInterceptor> tmpMap = new HashMap<>(id2InterceptorMap);
          tmpMap.put(id, interceptor);
  
          id2InterceptorMap = unmodifiableMap(tmpMap);
  
          List<MapInterceptor> tmpInterceptors = new ArrayList<>(interceptors);
          tmpInterceptors.add(interceptor);
  
          interceptors = unmodifiableList(tmpInterceptors);
      }