javax.net.ssl.SSLException:无法识别的ssl消息，纯文本连接

我正在尝试从spring应用程序发送邮件。我已经包含了所有jar文件，但它显示了以下异常：

javax.mail.MessagingException: Exception reading response;
  nested exception is:
    javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
    at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1611)
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1369)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:412)
    at javax.mail.Service.connect(Service.java:310)
    at javax.mail.Service.connect(Service.java:169)
    at javax.mail.Service.connect(Service.java:118)
    at javax.mail.Transport.send0(Transport.java:188)
    at javax.mail.Transport.send(Transport.java:118)
    at org.symb.leavemanagement.mail.SampleMail.sentMail(SampleMail.java:65)
    at org.symb.leavemanagement.controller.AdminController.processRegistratingUser(AdminController.java:196)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:175)
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:421)
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:409)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:774)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:560)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:987)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:309)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
    at java.lang.Thread.run(Thread.java:722)
Caused by: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
    at sun.security.ssl.InputRecord.handleUnknownRecord(InputRecord.java:541)
    at sun.security.ssl.InputRecord.read(InputRecord.java:374)
    at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:893)
    at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1294)
    at sun.security.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:848)
    at sun.security.ssl.AppInputStream.read(AppInputStream.java:102)
    at com.sun.mail.util.TraceInputStream.read(TraceInputStream.java:110)
    at java.io.BufferedInputStream.fill(BufferedInputStream.java:235)
    at java.io.BufferedInputStream.read(BufferedInputStream.java:254)
    at com.sun.mail.util.LineInputStream.readLine(LineInputStream.java:88)
    at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1589)
    ... 38 more

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您正在尝试与非SSL端点进行SSL连接。如果你改变，它应该会工作

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我发现大多数关于将电子邮件与Outlook/Thunderbird/etc集成的教程都将SSL/TSL称为非SSL连接。一般来说，我发现只有smtp端口465是SSL（这可能会改变，但这是正常的）。587是TSL（无SSL），25是普通

“TLS（无SSL）”基本上没有意义。SMTPS连接由SSL或TLS保护。虽然出于向后兼容的原因，仍在使用SMTPS的465保留。465和587之间的真正区别在于587支持STARTTLS命令，因此支持明文和TLS/SSL。为什么要重新打开它？它是复制品。