private static <T> Object getLoadClassLock(Class<T> clazz) {
    Object lock = CLASS_LOCKS.get(clazz);
    if (lock == null) {
      Object newLock = new Object();
      lock = CLASS_LOCKS.putIfAbsent(clazz, newLock);
      if (lock == null) {
        lock = newLock;
      }
    }
    return lock;
  }
Get extension class list order by {@link Order}
src/main/java/com/eudemon/ratelimiter/extension/ExtensionLoader.java