I want to develop a project in java & may be in Linux to download web pages n keep track of those web pages which are changing.
First how to download the pages?
Next how do I come to know whether a web page is changing or not?
For example , if i have www.google.com
in my database and if I had subscribed for that page, so how do I come to know that google has changed ?
what are the parameters that I should look that I come to know whether google has changed when the server periodically downloads it ?
Do I need to calculate the md5 of the page?