var drawingToolOldOnload = window.onContentLoad;
window.onContentLoad = function()
{
    if (typeof drawingToolOldOnload == 'function')
    {
         drawingToolOldOnload();
    }
    window.drawingToolInstance = new drawingTool();
    drawingToolInstance.init();
}

drawingTool = function ()
{

}

drawingTool.prototype.init = function()
{
    this.preventSessionTimeout();
}


drawingTool.prototype.preventSessionTimeout = function()
{
    if (!sessionRefreshUrl)
    {
        return;
    }
    var self = this
    this.sessionTimer = setTimeout(
        function() {
            loadXmlHttp( sessionRefreshUrl, function(){} );
            self.preventSessionTimeout();
        }
    ,
    30000
    );
}