private static @Nullable DirectBufferWrapper fromCache(CachedBuffer lastBuffer, long page) {
    if (lastBuffer != null && !lastBuffer.myWrapper.isReleased() &&
        lastBuffer.myLastPage == page) {
      return lastBuffer.myWrapper;
    }
    return null;
  }
private static @Nullable DirectBufferWrapper fromCache(CachedBuffer lastBuffer, long page)