之前在社区中看到了jfinal-mail-plugin这个组件，可以简单的进行邮件发送；简单的尝试了下最基本的邮件发送是没问题的，忘记当时的jfinal是哪一个版本了（jfinal版本更新太快了），现在我再重新走这个功能的时候发现报错，经过几次测试后发现在4.2版本是好的
4.8（当前使用版本）报错（好像是什么使用证书错误）
unable to find valid certification path to requested target com.jfplugin.mail.exception.MailSendException: 邮件发送失败！ at com.jfplugin.mail.MailPro.send(MailPro.java:91) at com.jfplugin.mail.MailPro.send(MailPro.java:56) at com.jfplugin.mail.MailKit.send(MailKit.java:61) at com.qc.future.cms.business.common.CommonController.sendMail(CommonController.java:45) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at com.jfinal.aop.Invocation.invoke(Invocation.java:97) at com.jfinal.core.ActionHandler.handle(ActionHandler.java:89) at com.jfinal.plugin.druid.DruidStatViewHandler.handle(DruidStatViewHandler.java:81) at com.qc.future.org.hanlder.WebSocketHandler.handle(WebSocketHandler.java:14) at com.jfinal.ext.handler.ContextPathHandler.handle(ContextPathHandler.java:48) at com.jfinal.core.JFinalFilter.doFilter(JFinalFilter.java:90) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84) at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) at io.undertow.servlet.handlers.ServletChain$1.handleRequest(ServletChain.java:68) at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) at io.undertow.servlet.handlers.RedirectDirHandler.handleRequest(RedirectDirHandler.java:68) at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:132) at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60) at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77) at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.servlet.handlers.SessionRestoringHandler.handleRequest(SessionRestoringHandler.java:119) at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:269) at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:78) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:133) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:130) at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48) at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:249) at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:78) at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:99) at io.undertow.server.Connectors.executeRootHandler(Connectors.java:376) at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:830) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) Caused by: com.jfplugin.mail.exception.MailSendException: Mail server connection failed. Failed messages: 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; message exceptions (1) are: Failed message 1: 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.jfplugin.mail.core.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:380) at com.jfplugin.mail.core.JavaMailSenderImpl.send(JavaMailSenderImpl.java:320) at com.jfplugin.mail.core.JavaMailSenderImpl.send(JavaMailSenderImpl.java:316) at com.jfplugin.mail.MailPro.send(MailPro.java:89) ... 45 more Caused by: 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:1934) at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:638) at javax.mail.Service.connect(Service.java:295) at com.jfplugin.mail.core.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:369) ... 48 more 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:1946) at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:316) at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:310) at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1639) at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:223) at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1037) at sun.security.ssl.Handshaker.process_record(Handshaker.java:965) at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1064) at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1367) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1395) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1379) at com.sun.mail.util.SocketFetcher.configureSSLSocket(SocketFetcher.java:507) at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:238) at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1900) ... 51 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:397) at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:302) at sun.security.validator.Validator.validate(Validator.java:262) 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:1621) ... 61 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:141) at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126) at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280) at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:392) ... 67 more
4.2不报错功能能正常使用，邮件也能正常发送，邮件接收者也能接收到邮件
