private function _getHtmlForServerVariables($serverVars, $serverVarsSession)
{
// filter
$filterValue = !empty($_REQUEST['filter']) ? $_REQUEST['filter'] : '';
$output = Template::get('filter')->render(array('filterValue' => $filterValue));
$output .= '<table id="serverVariables" class="data filteredData noclick">';
$output .= Template::get('server/variables/variable_table_head')->render();
$output .= '<tbody>';
$output .= $this->_getHtmlForServerVariablesItems($serverVars, $serverVarsSession);
$output .= '</tbody>';
$output .= '</table>';
return $output;
}