Get and display data from server using ajax -

I am trying to learn Ajax, but I have a hard time getting it.

I have a Java servlet that will give me data from DB, and I am trying to create a simple web page which constantly asks for an update every 5 seconds, and then reload the page Displays without doing I also do not want to do this on state preparedness, but only once every 5 seconds.

  // xmlHttp = xmlHttpRequest Object Function Process () {try (if xmlHttp .readyState == 4 || xmlHttp.readyState == 0} {xmlHttp.open ("GET", 'LocalHost : 8080 ', is true); // handleServerResponse (); // Get data from the server, not on the state change, but always? Set intern ('process ()', 5000); } Other {setTimeout ('process ()', 5000); }} Hold (e) {warning ('main process did not work'); Warning (e.toString ()); }}  

I am uncertain how can I complete it. what is missing?

The following steps include obtaining data from the server

An AJAX request Create an object and open the connection

and then send the request to the server

The server continually sends the response when processing on the request. East. 200 will be sent when the request is successful and 404 when it can not find the resource. The prepared state tells us how the state of request has 5 states that tell us the status of our request with the server.

When is ready 4 and the situation is 200. Your request on the server is successful and you receive a response in request.responseHTML or request.responseXML . Which you use for processing it

windown.onload = initialize; Function initialize () {setInterval (process, 5000); } Request request; Function Process () {Request = getAJAXREQUETOBJECT; Request.open ("receive", "url", true); request. Request.send (true); } Function requestresponse () {if (request.readystate == 4 & request.status == 200} {// request.response manipulate with HTML or request.responseXML}} < / Li>