public static void clearCache() {
    long stamp = ourInternerLock.writeLock();
    try {
      ourInterner.forEach((type, cachedType) -> {
        // clear references to file types to aid plugin unloading
        cachedType.fileType = null;
      });
      ourInterner.clear();
    } finally {
      ourInternerLock.unlockWrite(stamp);
    }
  }
public static void clearCache()