如何验证文件是否已在android中完全下载？

I have a reference application that downloads an sql lite file in the beginning to use to reference the data. I need to have a way to verify if the file has downloaded completely. I was saving the file length after the file downloads and putting it into preferences and checking against the actual file at the start of the application. I'm adding tables and other data to the database now and cannot use that method. What do I use?I have a reference application that downloads a