var reqXML;
    
function LoadXMLDoc(url){
  if (window.XMLHttpRequest){ //Mozilla, Firefox, Opera 8.01, Safari
    reqXML = new XMLHttpRequest(); 
    reqXML.onreadystatechange = BuildXMLResults; 
    reqXML.open("GET", url, true); 
    reqXML.send(null); 
  }
  else if(window.ActiveXObject){ //IE
    reqXML = new ActiveXObject("Microsoft.XMLHTTP"); 
    if (reqXML) { 
      reqXML.onreadystatechange = BuildXMLResults; 
      reqXML.open("GET", url, true); 
      reqXML.send(); 
    } 
  }
  else{ //Older Browsers
    alert("Your Browser does not support Ajax!");
  }
} 

function BuildXMLResults(){
  if(reqXML.readyState == 4){ //completed state
    if(reqXML.status == 200){ //We got a sucess page back
         
      //Check to verify the message from the server 
      //alert(reqXML.responseText+' ** '+reqXML.responseText.indexOf("Session Updated - Server Time:"));
      //if(reqXML.responseText.indexOf("Session Updated - Server Time:") >= 0){
      if(reqXML.responseText.indexOf("aggiornata") >= 0){
				//window.status = reqXML.responseText; //display the message in the status bar
        SetTimer(); //restart timer
      }
      else{
        //display that that session expired
        alert("Your session appears to have expired. You may loose your current data.");
      }
    } 
    else{
      //display server code not be accessed
      alert("There was a problem retrieving the XML data:\n" + reqXML.statusText);
    }		
  }
}
      
function ConfirmUpdate(){
  //Ask them to extend
  //if(confirm("Your session is about to expire. Press 'OK' to renew your session.")){
    //load server side page if ok
    //LoadXMLDoc('sessionUpdater.jsp'); 
	var rnd=Math.random();
	rnd=Math.round(rnd*10000.0);
    LoadXMLDoc('SessionUpdaterServlet?rnd='+rnd); 
  //}
}      
      
var timerObj;
function SetTimer(){
  //How long before timeout (should be a few minutes before your server's timeout
  var dblMinutes = 10;
  //set timer to call function to confirm update 
  timerObj = setTimeout("ConfirmUpdate()",1000*60*dblMinutes);
}
      
//start the timer
SetTimer();