@北望沣渭 PrivateKey merchantPrivateKey = PemUtil.loadPrivateKey(new FileInputStream(crtFilePathStr + privateKeyFile)); AutoUpdateCertificatesVerifier verifier = new AutoUpdateCertificatesVerifier(         new WechatPay2Credentials(MERCHANT_ID, new PrivateKeySigner(MERCHANT_SERIAL_NO, merchantPrivateKey)),         APIV3_KEY.getBytes("utf-8")); WECHATPAY_SERIAL_NO = verifier.getValidCertificate().getSerialNumber().toString(16).toUpperCase(); _httpClient = WechatPayHttpClientBuilder.create()         .withMerchant(MERCHANT_ID, MERCHANT_SERIAL_NO, merchantPrivateKey)         .withValidator(new WechatPay2Validator(verifier))         .build(); 就是按照那个官方的例子里写的，这里边死活就是报 parameter error: empty Wechatpay-Serial 然后抛出去的异常信息里提示： Caused by: org.apache.http.HttpException: 应答的微信支付签名验证失败 我请求接口使用的是如下内容 JSONObject parmJson = new JSONObject(); parmJson.put("appid", APP_ID); parmJson.put("mch_id", MERCHANT_ID); parmJson.put("sub_appid", "wxc6d45bc83c029ffe"); parmJson.put("sub_mch_id", "1603522998"); String nonceStr = UUID.randomUUID().toString().trim().replaceAll("-", ""); parmJson.put("nonce_str", nonceStr); //parmJson.put("sign", ""); //签名，暂时屏蔽，据说v3接口会自动签名 parmJson.put("body", "营业收入"); parmJson.put("out_trade_no", "1234567890"); parmJson.put("total_fee", 100); //金额，单位分 parmJson.put("spbill_create_ip", "192.168.1.55"); parmJson.put("notify_url", "https://www.hui9.net/api/wxpay/payNotify"); parmJson.put("trade_type", "APP"); String parmStr = parmJson.toJSONString(); HttpPost httpPost = new HttpPost("https://api.mch.weixin.qq.com/pay/unifiedorder"); StringEntity reqEntity = new StringEntity(parmStr, ContentType.create("application/json", "utf-8")); httpPost.setEntity(reqEntity); httpPost.addHeader("Accept", "application/json"); httpPost.addHeader("Content-Type", "application/json"); httpPost.addHeader("Wechatpay-Serial", WECHATPAY_SERIAL_NO); CloseableHttpResponse response = getWxpayClient().execute(httpPost); int statusCode = response.getStatusLine().getStatusCode(); String respHtml = EntityUtils.toString(response.getEntity()); 关键代码就这么多。 麻烦指导一下，谢谢了！