微信支付接口开发>java -jar CertificateDownloader-1.2.0-jar-with-dependencies.jar -k 350681200209205718linguohui12345 -m 1614993157 -f apiclient_key.pem -s 327F789877CFEEB1B61B58B689431BAD9DF1C0DF -o .\  下载jar包然后cmd执行报错 apiV3key=[350681200209205718linguohui12345] privateKey file path=[apiclient_key.pem] merchant's certificate serial number=[327F789877CFEEB1B61B58B689431BAD9DF1C0DF] === download begin === javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target at sun.security.ssl.Alerts.getSSLException(Alerts.java:198) at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1958) at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:322) at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:316) at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1526) at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:215) at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1024) at sun.security.ssl.Handshaker.process_record(Handshaker.java:954) at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1065) at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1384) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1412) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1396) at org.apache.http.conn.ssl.SSLConnectionSocketFactory.createLayeredSocket(SSLConnectionSocketFactory.java:436) at org.apache.http.conn.ssl.SSLConnectionSocketFactory.connectSocket(SSLConnectionSocketFactory.java:384) at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:142) at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:376) at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:393) at org.apache.http.impl.execchain.MainClientExec.execute