title: How to detect file modification?
body: <p>I have a stored file containing some data. I want to detect if it has been modified, and then address the issue if necessary. </p>
  
  <p>I thought about controlling for the number of lines in the file, but I am stuck.</p>
  
  <p>Moreover, there is no method to perform this: <a href="http://developer.android.com/reference/java/io/File.html" rel="nofollow noreferrer">http://developer.android.com/reference/java/io/File.html</a>.</p>
  
  <p>Any ideas please?</p>