javax.mail.MessagingException: Could not connect to SMTP host: smtp.163.com, port: 465;

 nested exception is:

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 com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2211)

at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:740)

at javax.mail.Service.connect(Service.java:388)

at javax.mail.Service.connect(Service.java:246)

at javax.mail.Service.connect(Service.java:195)

at javax.mail.Transport.send0(Transport.java:254)

at javax.mail.Transport.send(Transport.java:124)

at com.yan.blog.utils.email.EmailSender.send(EmailSender.java:300)

at com.yan.blog.test.main(test.java:19)

Caused by: 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:192)

at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1949)

at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:302)

at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:296)

at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1509)

at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:216)

at sun.security.ssl.Handshaker.processLoop(Handshaker.java:979)

at sun.security.ssl.Handshaker.process_record(Handshaker.java:914)

at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1062)

at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1375)

at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1403)

at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1387)

at com.sun.mail.util.SocketFetcher.configureSSLSocket(SocketFetcher.java:626)

at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:400)

at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:238)

at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2175)

... 8 more

Caused by: 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.validator.PKIXValidator.doBuild(PKIXValidator.java:387)

at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:292)

at sun.security.validator.Validator.validate(Validator.java:260)

at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324)

at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:229)

at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:124)

at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1491)

... 19 more

Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:146)

at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:131)

at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)

at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:382)

... 25 more