/**
  * Initialize creditmemo state based on requested parameters
  *
  * @param Creditmemo $creditmemo
  * @param array $data
  * @return void
  */
 protected function initData($creditmemo, $data)
 {
     if (isset($data['shipping_amount'])) {
         $creditmemo->setBaseShippingAmount((double) $data['shipping_amount']);
     }
     if (isset($data['adjustment_positive'])) {
         $creditmemo->setAdjustmentPositive($data['adjustment_positive']);
     }
     if (isset($data['adjustment_negative'])) {
         $creditmemo->setAdjustmentNegative($data['adjustment_negative']);
     }
 }