/**
  * Retrieve Batch import model
  *
  * @return Mage_Dataflow_Model_Import_Export
  */
 public function getBatchImportModel()
 {
     if (is_null($this->_batchImport)) {
         $object = Mage::getModel('dataflow/batch_import');
         $this->_batchImport = Varien_Object_Cache::singleton()->save($object);
     }
     return Varien_Object_Cache::singleton()->load($this->_batchImport);
 }

 /**
  * Varien Objects Cache
  *
  * @param string $key optional, if specified will load this key
  * @return Varien_Object_Cache
  */
 public static function objects($key = null)
 {
     if (!self::$_objects) {
         self::$_objects = new Varien_Object_Cache();
     }
     if (is_null($key)) {
         return self::$_objects;
     } else {
         return self::$_objects->load($key);
     }
 }

 /**
  * Singleton factory
  *
  * @return Varien_Object_Cache
  */
 public static function singleton()
 {
     if (!self::$_instance) {
         self::$_instance = new self();
     }
     return self::$_instance;
 }

 public function getConfigModel()
 {
     if (is_null($this->_configModel)) {
         $object = Mage::getModel('core/config_data');
         $this->_configModel = Varien_Object_Cache::singleton()->save($object);
     }
     return Varien_Object_Cache::singleton()->load($this->_configModel);
 }

 /**
  * Retrieve Batch import model
  *
  * @return Mage_Dataflow_Model_Import_Export
  */
 public function getBatchImportModel()
 {
     if (is_null($this->_batchImport)) {
         $object = Mage::getModel('Mage_Dataflow_Model_Batch_Import');
         $object->setBatchId($this->getId());
         $this->_batchImport = Varien_Object_Cache::singleton()->save($object);
     }
     return Varien_Object_Cache::singleton()->load($this->_batchImport);
 }