我在AWS申请的CA证书，配置生效后，用MQTTX客户端请求mqtts 的 8883端口能连接，但是通过 org.eclipse.paho.client.mqttv3 连接报错 ，但是查询证书，显示的是EMQ的自签名证书。
报错内容：
MqttException (0) - javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at org.eclipse.paho.client.mqttv3.internal.ExceptionHelper.createMqttException(ExceptionHelper.java:38)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:715)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266)
at java.util.concurrent.FutureTask.run(FutureTask.java)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:750)
Caused by: javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.ssl.Alert.createSSLException(Alert.java:131)
at sun.security.ssl.TransportContext.fatal(TransportContext.java:331)
at sun.security.ssl.TransportContext.fatal(TransportContext.java:274)
at sun.security.ssl.TransportContext.fatal(TransportContext.java:269)
at sun.security.ssl.CertificateMessage$T13CertificateConsumer.checkServerCerts(CertificateMessage.java:1356)
at sun.security.ssl.CertificateMessage$T13CertificateConsumer.onConsumeCertificate(CertificateMessage.java:1231)
at sun.security.ssl.CertificateMessage$T13CertificateConsumer.consume(CertificateMessage.java:1174)
at sun.security.ssl.SSLHandshake.consume(SSLHandshake.java:377)
at sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:444)
at sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:422)
at sun.security.ssl.TransportContext.dispatch(TransportContext.java:182)
at sun.security.ssl.SSLTransport.decode(SSLTransport.java:152)
at sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1401)
at sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1309)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:440)
at org.eclipse.paho.client.mqttv3.internal.SSLNetworkModule.start(SSLNetworkModule.java:108)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:701)
... 8 more
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:456)
at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:323)
at sun.security.validator.Validator.validate(Validator.java:271)
at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:315)
at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:223)
at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:129)
at sun.security.ssl.CertificateMessage$T13CertificateConsumer.checkServerCerts(CertificateMessage.java:1340)
... 20 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:148)
at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:129)
at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)
at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:451)
... 26 more
执行命令： openssl s_client -connect xxxxxxx:8883 -showcerts
CONNECTED(00000006)
depth=1 C = CN, ST = hangzhou, O = EMQ, CN = RootCA
verify error:num=19:self-signed certificate in certificate chain
verify return:1
depth=1 C = CN, ST = hangzhou, O = EMQ, CN = RootCA
verify return:1
depth=0 C = CN, ST = hangzhou, O = EMQ, CN = Server
verify return:1
---
Certificate chain
0 s:C = CN, ST = hangzhou, O = EMQ, CN = Server
i:C = CN, ST = hangzhou, O = EMQ, CN = RootCA
a:PKEY: rsaEncryption, 2048 (bit); sigalg: RSA-SHA256
v:NotBefore: May 8 08:07:05 2020 GMT; NotAfter: May 6 08:07:05 2030 GMT
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
1 s:C = CN, ST = hangzhou, O = EMQ, CN = RootCA
i:C = CN, ST = hangzhou, O = EMQ, CN = RootCA
a:PKEY: rsaEncryption, 2048 (bit); sigalg: RSA-SHA256
v:NotBefore: May 8 08:06:52 2020 GMT; NotAfter: May 6 08:06:52 2030 GMT
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
---
Server certificate
subject=C = CN, ST = hangzhou, O = EMQ, CN = Server
issuer=C = CN, ST = hangzhou, O = EMQ, CN = RootCA
---
No client certificate CA names sent
Peer signing digest: SHA256
Peer signature type: RSA-PSS
Server Temp Key: X25519, 253 bits
---
SSL handshake has read 2205 bytes and written 400 bytes
Verification error: self-signed certificate in certificate chain
---
New, TLSv1.3, Cipher is TLS_AES_256_GCM_SHA384
Server public key is 2048 bit
This TLS version forbids renegotiation.
Compression: NONE
Expansion: NONE
No ALPN negotiated
Early data was not sent
Verify return code: 19 (self-signed certificate in certificate chain)
---
closed