ImageIO.read 状态:

如果没有注册的 ImageReader 声称能够读取结果流，则返回 null.

If no registered ImageReader claims to be able to read the resulting stream, null is returned.

如果 bImageFromConvert 为空，您将得到您显示的异常.所以这几乎可以肯定正在发生.您应该查看从 rsvalue.getBytes(10) 返回的数据 - 看看它是否不完整、损坏或类似.一个起点是将其写入文件，然后查看是否可以使用图片查看器打开它.

And if bImageFromConvert is null, you'll get the exception you've shown. So that's almost certainly what's happening. You should look at the data returned from rsvalue.getBytes(10) - see whether it's incomplete, corrupt or something similar. A starting point would be to write it to a file and see whether you can open it using a picture viewer.