@Autowired
AlipayClient alipayClient;

public PaymentStatus checkAlipayPayment(PaymentInfo paymentInfo){

    System.out.println(“开始主动检查支付状态，paymentInfo.toString() = ” + paymentInfo.toString());
    //先检查当前数据库是否已经变为“已支付状态”
    if(paymentInfo.getId()==null){
        System.out.println(“outTradeNo:”+paymentInfo.getOutTradeNo()  );
        paymentInfo = getPaymentInfo(paymentInfo);
    }
    if (paymentInfo.getPaymentStatus()== PaymentStatus.PAID){
        System.out.println(“该单据已支付:”+paymentInfo.getOutTradeNo());
        return PaymentStatus.PAID;
    }

    //如果不是已支付，继续去查询alipay的接口
    System.out.println(“%% % % 查询alipay的接口”  );
    AlipayTradeQueryRequest alipayTradeQueryRequest=new AlipayTradeQueryRequest();
    alipayTradeQueryRequest.setBizContent(“{\”out_trade_no\”:\””+paymentInfo.getOutTradeNo()+“\”}”);
    AlipayTradeQueryResponse response=null;
    try {
        response = alipayClient.execute(alipayTradeQueryRequest);
    } catch (AlipayApiException e) {
        e.printStackTrace();
    }

 
    if(response.isSuccess()){
        String tradeStatus = response.getTradeStatus();

        if (“TRADE_SUCCESS”.equals(tradeStatus)){
            System.out.println(“支付完成  ======================  ”    );
            //如果结果是支付成功 ,则更新支付状态
            PaymentInfo paymentInfo4Upt=new PaymentInfo();
            paymentInfo4Upt.setPaymentStatus(PaymentStatus.PAID);
            paymentInfo4Upt.setCallbackTime(new Date());
            paymentInfo4Upt.setCallbackContent(response.getBody());
            paymentInfo4Upt.setId(paymentInfo.getId());
            paymentInfoMapper.updateByPrimaryKeySelective(paymentInfo4Upt);

            // 然后发送通知给订单
            sendPaymentResult(paymentInfo,“success”);
            return PaymentStatus.PAID;
        }else{
            System.out.println(“支付尚未完成 ？？？？？？？？？？ ”    );
            return PaymentStatus.UNPAID;
        }
    }else{
        System.out.println(“支付尚未完成 ？？？？？？？？？？ ”    );
        return    PaymentStatus.UNPAID;
    }

}