// $Id:$ 
var SERVLET_NAME="AjaxServlet";

function AJAXInteraction( parameters, callback )
{
    var req = init();
    req.onreadystatechange = processRequest;

    function init()
    {
        if ( window.XMLHttpRequest )
            return new XMLHttpRequest();
        else if ( window.ActiveXObject )
            return new ActiveXObject("Microsoft.XMLHTTP");
    }

    function processRequest()
    {
        try
        {
            if ( req.readyState == 4 && req.status == 200 && callback )
                callback(req.responseText);
        }
        catch ( e )
        {
            callback("Error :" + e.description);
        }
    }

    this.doGet = function()
    {
        req.open("GET", SERVLET_NAME+"?" + parameters, true);
        req.send(null);
    }
    
    this.doPost = function()
    {
        req.open("POST", SERVLET_NAME, true);
        req.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        req.setRequestHeader("Content-length", parameters.length);
        req.send(parameters);
    }
}