public JsapiService getJsapiService() {
    Config config = new RSAPublicKeyConfig.Builder()
            .merchantId(merchantId)
            .privateKeyFromPath(privateKeyUrl)
            .publicKeyFromPath(publicKeyUrl)
            .publicKeyId(publicKeyId)
            .merchantSerialNumber(merchantSerialNumber)
            .apiV3Key(apiV3Key)
            .build();
    config.createSigner().getAlgorithm();
    return new JsapiService.Builder().config(config).build();
}