The code snippet below shows the use of NetworkCredential...
I'm curious over the object (networkCredential in this case) it creates
because it was used once only for authentication purposes... (exactly
before accessing the webpage...) Do you have any idea how is this going
to be implemented in Java? Thanks...

   void Page_Load(Object sender, EventArgs e) {
       XmlDocument doc = new XmlDocument();
       NetworkCredential networkCredential = new
NetworkCredential("username","password"); ==> THIS IS WHAT I MEAN...

   HttpWebRequest HttpWReq = (HttpWebRequest)WebRequest.Create(
     "http://api.keyworddiscovery.com/free.php?q="
     + HttpUtility.UrlEncode(Request.Form["query"])
     );
   HttpWReq.PreAuthenticate = true;

   HttpWReq.Credentials = networkCredential;

   HttpWebResponse HttpWResp =
(HttpWebResponse)HttpWReq.GetResponse();

   if (HttpWResp.StatusCode == HttpStatusCode.OK) {
     doc.Load(HttpWResp.GetResponseStream());
   }

       XslTransform trans = new XslTransform();
       trans.Load(Server.MapPath("output_template.xsl"));

       xml1.Document = doc;
       xml1.Transform = trans;
   }

wasn't it you in that last post on the futility of making Internet
requests?