public void processQueue() {
    ConcurrentMap<VirtualFile, FileViewProvider> map = myVFileToViewProviderMap.get();
    if (map == null) return;

    // myVFileToViewProviderMap is in fact ConcurrentWeakValueHashMap.
    // calling map.remove(unrelated-object) calls ConcurrentWeakValueHashMap#processQueue under the hood
    map.remove(NULL);
  }
public void processQueue()