public function displayCache()
 {
     require_once 'Services/Form/classes/class.ilPropertyFormGUI.php';
     require_once 'Services/GlobalCache/classes/class.ilGlobalCache.php';
     $this->checkDisplayMode('setup_cache');
     /**
      * @var $ini ilIniFile
      */
     $ini = $this->setup->getClient()->ini;
     $cache_form = new ilPropertyFormGUI();
     $cache_form->setTitle($this->lng->txt('global_cache_configuration'));
     $cache_form->addCommandButton('saveCache', $this->lng->txt('save'));
     $cache_form->setFormAction('setup.php?cmd=gateway');
     $activate_global_cache = 'activate_global_cache';
     $global_cache_service_type = 'global_cache_service_type';
     $activate_cache = new ilCheckboxInputGUI($this->lng->txt($activate_global_cache), $activate_global_cache);
     $activate_cache->setChecked($ini->readVariable('cache', $activate_global_cache));
     $service_type = new ilRadioGroupInputGUI($this->lng->txt($global_cache_service_type), $global_cache_service_type);
     $some_inactive = false;
     $message = '';
     foreach (ilGlobalCache::getAllTypes() as $type) {
         $option = new ilRadioOption($this->lng->txt($global_cache_service_type . '_' . $type->getServiceType()), $type->getServiceType());
         $option->setInfo($this->lng->txt('global_cache_install_info_' . $type->getServiceType()));
         if (!$type->isCacheServiceInstallable()) {
             $option->setDisabled(true);
             $message .= $this->lng->txt($global_cache_service_type . '_' . $type->getServiceType()) . ': ' . $type->getInstallationFailureReason() . '; ';
             $some_inactive = true;
         }
         $service_type->addOption($option);
     }
     if ($some_inactive) {
         $service_type->setAlert($message);
         ilUtil::sendInfo($this->lng->txt('global_cache_supported_services'));
     }
     $service_type->setValue($ini->readVariable('cache', $global_cache_service_type));
     $activate_cache->addSubItem($service_type);
     $cache_form->addItem($activate_cache);
     $this->tpl->setVariable('SETUP_CONTENT', $cache_form->getHTML());
 }