how to send the html of a site to java by pressing ctrl+u on the site? [closed]

I'm trying to analyze the html of a site through java simply by pressing ctrl + u, I thought that through a "keylistener" the program can check if I clicked ctrl + u or not, the real problem is how to send the html to java. Searching I found classes to analyze the html of a site by giving the url to a method, except that obviously it does not work for sites that require logins, or for sites that change something with each page update. I have no ideas on how to do it if someone has a solution I would be grateful to him, even some solution with other languages like php which should be more appropriate for this kind of thing?
P.S. Sorry my bad English