public function getAdapter()
    {
        /**
         * Check for an adapter being defined. if not, fetch the default adapter.
         */
        if ($this->_adapter === null) {
            $this->_adapter = Zend_Db_Table_Abstract::getDefaultAdapter();
            if (null === $this->_adapter) {

                throw new Zend_Validate_Exception('No database adapter present');
            }
        }
        return $this->_adapter;
    }