Sending requests and receiving responses is not enough when we have to emulate browsing through a website. For example, we might need to login, capture and carry-on the cookies to preserve the session, follow the redirects, make requests to get dynamic content... in the same way as a real web browser.
HttpSessionis a tool just for that. It sends requests for you, handles 301 and 302 redirections automatically, reads and preserves cookies across the requests, and so on.
Usage is simple:
HttpSession session = new HttpSession();
HttpRequest request = HttpRequest.get("www.facebook.com");
// request is sent, and response is received
// process the HTML page
String page = session.getPage();
// create a new request
HttpRequest newRequest = HttpRequest.post(formAction);
HttpSessioninstance handles all the cookies, allowing the session to be tracked while browsing using HTTP and supports keep-alive persistent connections.