原因
项目需要实现自动提现到支付宝，涉及到资金类支出接口 ，所以需要升级密钥为公钥证书；
参考文档：支付宝密钥相关文档
准备证书
生成csr时保存下来的2个.txt(应用公钥没啥用，应用私钥需要妥善保存)，支付宝平台下载 3个.csr（应用公钥证书、支付宝公钥证书、支付宝根证书）；
代码修改
升级SDK版本，低版本SDK不支持证书模式<dependency><groupId>com.alipay.sdk</groupId><artifactId>alipay-sdk-java</artifactId><version>4.11.54.ALL</version></dependency>
升级初始化方式
private static final String URL = "/gateway.do";/*** 数据类型*/public static final String DATA_FORMAT = "json";public static final String CHARSET = CharsetUtil.UTF_8;/*** 签名类型*/public static final String SIGN_TYPE = "RSA2";@Beanpublic AlipayClient aplipayClient(AliPayProperties properties) {try {CertAlipayRequest certAlipayRequest = new CertAlipayRequest();certAlipayRequest.setServerUrl(URL);certAlipayRequest.setAppId(properties.getAppId());//应用私钥，生成csr文件时，保存到本地的私钥txt文件certAlipayRequest.setPrivateKey(readKey(properties.getMerchantPrivateKeyPath()));certAlipayRequest.setFormat(DATA_FORMAT);certAlipayRequest.setCharset(CHARSET);certAlipayRequest.setSignType(SIGN_TYPE);//应用公钥证书路径certAlipayRequest.setCertPath(properties.getMerchantCertPath());//支付宝公钥证书路径certAlipayRequest.setAlipayPublicCertPath(properties.getAlipayCertPath());//支付宝根证书路径certAlipayRequest.setRootCertPath(properties.getAlipayRootCertPath());return new DefaultAlipayClient(certAlipayRequest);} catch (AlipayApiException e) {AssertUtils.fail("AlipayClient初始化失败："+e.getMessage());return null;}}private String readKey(String path) {if (FileUtil.exist(path)) {FileReader reader = new FileReader(path);return reader.readString();} else {AssertUtils.fail("缺少支付宝应用密钥文件");}return null;}
alipayClient.execute改成 alipayClient.certificateExecute回调验签方法 AlipaySignature.rsaCheckV1 升级为 AlipaySignature.rsaCertCheckV1
