APP微信支付实现

参考官方文档

设计到的API： 统一下单API、支付结果通知API和查询订单API

下面代码是请求预支付ID

        // 构建下单bean
        final WxPayUnifiedOrderBean unifiedOrderBean = new WxPayUnifiedOrderBean();
        unifiedOrderBean.setAppid(wxPayConfig.getAppId());
        unifiedOrderBean.setMch_id(wxPayConfig.getMchId());
        unifiedOrderBean.setNonce_str(this.getNonceStr(16));
        unifiedOrderBean.setBody("支付");
        unifiedOrderBean.setOut_trade_no(order.getHubOrderNo());
        unifiedOrderBean.setTotal_fee(order.getTotalFee());
        unifiedOrderBean.setSpbill_create_ip(order.getSpbill_create_ip());
        unifiedOrderBean.setNotify_url(this.paymentProperties.getWeixin().getNotify_url());
        unifiedOrderBean.setSign(this.generateSignForPrePayId(unifiedOrderBean, wxPayConfig.getSecret()));

        // 请求统一下单接口
        final WxPayPrePayBean bean = this.requestWx(unifiedOrderBean);

/**
     * 请求统一下单接口
     *
     * @param unifiedOrderBean
     * @return
     */
    private WxPayPrePayBean requestWx(final WxPayUnifiedOrderBean unifiedOrderBean) {

        final XStream xStream = new XStream(new DomDriver("UTF-8", new NoNameCoder()));
        xStream.autodetectAnnotations(true);
        final String postXml = xStream.toXML(unifiedOrderBean);

        // 发送请求
        final HttpHeaders headers = new HttpHeaders();
        final MediaType type = MediaType.parseMediaType("application/x-www-form-urlencoded; charset=UTF-8");
        headers.setContentType(type);
        final HttpEntity<String> requestEntity = new HttpEntity<>(postXml, headers);

        final RestTemplate restTemplate = new RestTemplate();
        final ResponseEntity<String> responseEntity = restTemplate.postForEntity(
                PaymentConstant.WX_PREPARE_ORDER_URL, requestEntity, String.class);

        // 解析请求结果
        final XStream xStreamResult = new XStream(new DomDriver("UTF-8", new NoNameCoder()));
        xStreamResult.processAnnotations(WxPayPrePayBean.class);
        try {
            final String returnStr = new String(responseEntity.getBody().getBytes("ISO-8859-1"), "UTF-8");

            System.out.println(responseEntity.getBody());
            System.out.println(returnStr);
            final WxPayPrePayBean bean = (WxPayPrePayBean) xStreamResult.fromXML(returnStr);
            return bean;
        } catch (final Exception e) {
            e.printStackTrace();
            return null;
        }

    }