private boolean check(String mail, int N){
                               // mail = The mail
                               // N = The sum of the characters before the @ and including it him
		if(mail.substring(N) == "hotmail.com" || mail.substring(N) == "live.com" ||
				mail.substring(N) == "msn.com" || mail.substring(N) == "yahoo.com" ||
				mail.substring(N) == "gmail.com"){
			return true;
		} else {
			return false;
		}
	}

if (some boolean expression) {
   return true;
} else {
   return false;
}

return  (some boolean expression);