I'm trying to create an app that alerts me when a page changes (for example when they publish new contents ecc).
My first attempt was get the page html, store it and compare this code with the new one. I used: Simplest way to correctly load html from web page into a string in Java
My second attempt was using this: How to check whether a website has been updated and send a email?
But nothing worked because it alerts that pages as facebook.com (log in page) or google.com change every time I check (and it is impossible).
What can I do?