SpringBoot整合weixin-java-pay实现微信小程序支付的示例代码

<dependency>
  <groupId>com.github.binarywang</groupId>
  <artifactId>weinxin-java-pay</artifactId>
  <version>对应的版本号</version>
</dependency>

/**
 * @author: Eden4J
 * @Description: 微信支付商户信息配置类
 */
@Data
@Component
@RefreshScope
@ConfigurationProperties(prefix = "wechat.pay")
public class WeChatPayProperties {

    /**
     * 微信小程序或者微信公众号appId
     */
    private String appid;
    /**
     * 商户号
     */
    private String mchId;
    /**
     * 商户密钥
     */
    private String mchKey;
    /**
     * 商户证书序列号
     */
    private String serialNo;
    /**
     * apiV3Key
     */
    private String apiV3Key;
    /**
     * 证书
     */
    private String keyPath;
    /**
     * 商户私钥文件
     */
    private String privateKeyPath;

    /**
     * apiclient_cert.pem证书文件
     */
    private String privateCertPath;

    /**
     * 交易类型
     * JSAPI--公众号支付
     * NATIVE--原生扫码支付
     * APP--app支付
     */
    private String tradeType;
    /**
     * 支付结果异步通知回调地址
     */
    private String notifyUrl;
}

/**
 * @author: Eden4J
 * @Description: 微信支付配置类
 */
@Component
@ConditionalOnClass(WxPayService.class)
@RequiredArgsConstructor
public class WeChatPayConfig {
    private final WeChatPayProperties properties;

    @Bean
    @ConditionalOnMissingBean
    public WxPayConfig payConfig() {
        WxPayConfig payConfig = new WxPayConfig();
        payConfig.setAppId(StringUtils.trimToNull(this.properties.getAppid()));
        payConfig.setMchId(StringUtils.trimToNull(this.properties.getMchId()));
        payConfig.setMchKey(StringUtils.trimToNull(this.properties.getMchKey()));
        payConfig.setCertSerialNo(StringUtils.trimToNull(this.properties.getSerialNo()));
        payConfig.setApiV3Key(StringUtils.trimToNull(this.properties.getApiV3Key()));
        payConfig.setKeyPath(StringUtils.trimToNull(this.properties.getKeyPath()));
        payConfig.setPrivateKeyPath(StringUtils.trimToNull(this.properties.getPrivateKeyPath()));
        payConfig.setPrivateCertPath(StringUtils.trimToNull(this.properties.getPrivateCertPath()));
        payConfig.setTradeType(StringUtils.trimToNull(this.properties.getTradeType()));
        return payConfig;
    }

    @Bean
    public WxPayService wxPayService(WxPayConfig payConfig) {
        WxPayService wxPayService = new WxPayServiceImpl();
        wxPayService.setConfig(payConfig);
        return wxPayService;
    }
}

@Data
public class WxPayInfoVO implements Serializable {
    private String appId;
    private String timeStamp;
    private String nonceStr;
    private String packageValue;
    private String signType;
    private String paySign;
}

/**
 * @author: Eden4J
 * @Description: 微信支付相关工具类
 */
public class WxPayUtil {

    public static String sign(String signStr, PrivateKey privateKey) {
        Sign sign = SecureUtil.sign(SignAlgorithm.SHA256withRSA, privateKey.getEncoded(), null);
        return Base64.encode(sign.sign(signStr.getBytes()));
    }

    public static String buildMessage(String appId, String timeStamp, String nonceStr, String body) {
        return appId + "\n" + timeStamp + "\n" + nonceStr + "\n" + body + "\n";
    }

    public static AutoUpdateCertificatesVerifier getVerifier(WxPayConfig wxPayConfig) throws IOException {
        PrivateKey privateKey = PemUtils.loadPrivateKey(new ClassPathResource("apiclient_key.pem").getInputStream());
        AutoUpdateCertificatesVerifier verifier = new AutoUpdateCertificatesVerifier(
                new WxPayCredentials(wxPayConfig.getMchId(), new PrivateKeySigner(wxPayConfig.getCertSerialNo(), privateKey))
                , wxPayConfig.getApiV3Key().getBytes("utf-8")
        );
        return verifier;
    }

    /**
     * 验证签名
     *
     * @param certificate
     * @param message
     * @param signature
     * @return
     */
    public static boolean verify(AutoUpdateCertificatesVerifier certificate, byte[] message, String signature) {
        try {
            Signature sign = Signature.getInstance("SHA256withRSA");
            sign.initVerify(certificate.getValidCertificate());
            sign.update(message);
            return sign.verify(java.util.Base64.getDecoder().decode(signature));
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("当前Java环境不支持SHA256withRSA", e);
        } catch (SignatureException e) {
            throw new RuntimeException("签名验证过程发生了错误", e);
        } catch (InvalidKeyException e) {
            throw new RuntimeException("无效的证书", e);
        }
    }
}

@RestController
@RequestMapping("/请求路径")
@RequiredArgsConstructor
public class AppCustomerUserRechargeOrderController {
    private final IAppCustomerUserRechargeOrderService rechargeOrderService;

    @PostMapping("/preOrder")
    public Result<WxPayInfoVO> preOrder(@RequestParam("goodId") String goodId) {
        return Result.success(rechargeOrderService.preOrder(goodId));
    }

    // 支付回调
    @PostMapping("/back")
    public Map<String,String> back(@RequestBody Map body,HttpServletRequest request) {
      return rechargeOrderService.formalOrder(body, request);
    }
}

 @Override
    public WxPayInfoVO preRecharge(String goodId) {
        try {
            //看看是否有其他的业务逻辑
            // 调用微信的统一下单接口获取预支付单返回前端 createOrderV3(TradeTypeEnum tradeType, WxPayUnifiedOrderV3Request request)
            WxPayUnifiedOrderV3Request payRequest = new WxPayUnifiedOrderV3Request();
            payRequest.setOutTradeNo(rechargeNo);//系统充值订单号
            payRequest.setDescription(goodsPackage.getPackageName());
            //订单失效时间
            SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX");
            payRequest.setTimeExpire(dateFormat.format(DateUtil.offset(new Date(), DateField.HOUR_OF_DAY, 1)));
            WxPayUnifiedOrderV3Request.Payer payer = new WxPayUnifiedOrderV3Request.Payer();
            payer.setOpenid(userAccount.getOpenId());
            payRequest.setPayer(payer);
            WxPayUnifiedOrderV3Request.Amount amount = new WxPayUnifiedOrderV3Request.Amount();
            amount.setTotal(rechargeOrder.getTotalAmount().multiply(BigDecimal.valueOf(100)).intValue());
            amount.setCurrency("CNY");
            payRequest.setAmount(amount);
            payRequest.setNotifyUrl(weChatPayProperties.getNotifyUrl());
            WxPayUnifiedOrderV3Result.JsapiResult jsapiResult = wxPayService.createOrderV3(TradeTypeEnum.JSAPI, payRequest);
            String encode = WxPayUtil.sign(WxPayUtil.buildMessage(weChatPayProperties.getAppid(), jsapiResult.getTimeStamp(), jsapiResult.getNonceStr(), jsapiResult.getPackageValue())
                    , PemUtils.loadPrivateKey(new ClassPathResource("apiclient_key.pem").getInputStream()));
            WxPayInfoVO payInfoVO = PojoUtil.exchangePojo(jsapiResult, WxPayInfoVO.class);
            payInfoVO.setPaySign(encode);
            return payInfoVO;
        } catch (WxPayException e) {
            e.printStackTrace();
            throw new BizException("微信支付失败", e);
        } catch (IOException e) {
            e.printStackTrace();
            throw new BizException("微信支付失败", e);
        }
    }

    @Override
    public Map<String, String> createFormalOrder(Map body, HttpServletRequest request) {
        try {
            Map<String, String> resultMap = new HashMap<>();
            resultMap.put("code", "FAIL");
            ObjectMapper objectMapper = new ObjectMapper();
            try {
            	//官方文档中有说明切记不要改变原始报文主体，如果使用JSONObject接收的话，不能使用JSON转换出来的字符串，会出现验签错误的情况，请注意
                String data = objectMapper.writeValueAsString(body);
                SignatureHeader header = new SignatureHeader();
                header.setTimeStamp(request.getHeader("Wechatpay-Timestamp"));
                header.setNonce(request.getHeader("Wechatpay-Nonce"));
                header.setSignature(request.getHeader("Wechatpay-Signature"));
                header.setSerial(request.getHeader("Wechatpay-Serial"));
                WxPayNotifyV3Result notifyV3Result =wxPayService.parseOrderNotifyV3Result(data, header);
                WxPayNotifyV3Result.DecryptNotifyResult decryptNotifyResult = notifyV3Result.getResult();//解密后的数据
                    if ("SUCCESS".equalsIgnoreCase(decryptNotifyResult.getTradeState())) {
                        resultMap.put("code", "SUCCESS");
                    }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return resultMap;
        } catch (Exception e) {
            e.printStackTrace();
            throw new BizException("微信支付成功回调失败", e);
        }
    }