### Question:
PayServiceImpl implements PayService { @Override public RefundResponse refund(OrderDTO orderDTO) { RefundRequest refundRequest = new RefundRequest(); refundRequest.setOrderId(orderDTO.getOrderId()); refundRequest.setOrderAmount(orderDTO.getOrderAmount().doubleValue()); refundRequest.setPayTypeEnum(BestPayTypeEnum.WXPAY_H5); log.info("【微信退款】request={}", JsonUtil.toJson(refundRequest)); RefundResponse refundResponse = bestPayService.refund(refundRequest); log.info("【微信退款】response={}", JsonUtil.toJson(refundResponse)); return refundResponse; }  @Override PayResponse create(OrderDTO orderDTO); @Override PayResponse notify(String notifyData); @Override RefundResponse refund(OrderDTO orderDTO);  }### Answer:
@Test public void refund() { OrderDTO orderDTO = orderService.findOne("1499592887470659070"); payService.refund(orderDTO); }