使用带有代理的 Spring Boot 和 JavaMailSender 发送邮件

Question

I am trying to send email using JavaMailSender in spring boot. I have tried almost everything but still getting this error. Please suggest me what should I do In order to get my code working? Thanks!!!

here is my code for sending an email.

public void prepareAndSend(String recipient, String message) {
    SimpleMailMessage mailMessage = new SimpleMailMessage();
    mailMessage.setFrom("xxx@gmail.com");
    mailMessage.setTo(recipient);
    mailMessage.setSubject("test");
    mailMessage.setText(message);
    javaMailSender.send(mailMessage);
}

Application.properties file

spring.mail.host=smtp.gmail.com
spring.mail.port=587
spring.mail.username=*******
spring.mail.password= *******

#mail properties
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true

-Dhttp.proxyHost=192.168.15.1
-Dhttp.proxyPort=2120 
-Dhttps.proxyHost=192.168.15.1
-Dhttps.proxyPort=2120
-Dhttps.proxySet=true 
-Dhttp.proxySet=true

server.use-forwarded-headers=true

I am getting the following error Exception when I try to run the code

2018-12-14 11:38:03.832 ERROR 2540 --- [nio-9090-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.mail.MailSendException: Mail server connection failed; nested exception is javax.mail.MessagingException: Unknown SMTP host: smtp.gmail.com;
  nested exception is:
    java.net.UnknownHostException: smtp.gmail.com. Failed messages: javax.mail.MessagingException: Unknown SMTP host: smtp.gmail.com;
  nested exception is:
    java.net.UnknownHostException: smtp.gmail.com; message exceptions (1) are:
Failed message 1: javax.mail.MessagingException: Unknown SMTP host: smtp.gmail.com;
  nested exception is:
    java.net.UnknownHostException: smtp.gmail.com] with root cause

java.net.UnknownHostException: smtp.gmail.com
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184) ~[na:1.8.0_172]
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) ~[na:1.8.0_172]
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_172]
    at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_172]
    at java.net.Socket.connect(Socket.java:538) ~[na:1.8.0_172]
    at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:319) ~[mail-1.4.5.jar:1.4.5]
    at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:233) ~[mail-1.4.5.jar:1.4.5]
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1938) ~[mail-1.4.5.jar:1.4.5]
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:642) ~[mail-1.4.5.jar:1.4.5]
    at javax.mail.Service.connect(Service.java:295) ~[mail-1.4.5.jar:1.4.5]
    at org.springframework.mail.javamail.JavaMailSenderImpl.connectTransport(JavaMailSenderImpl.java:501) ~[spring-context-support-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:421) ~[spring-context-support-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:307) ~[spring-context-support-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:296) ~[spring-context-support-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at com.bharti.firstspringbootproject.service.UserService.prepareAndSend(UserService.java:46) ~[classes/:na]
    at com.bharti.firstspringbootproject.controller.AuthenticateController.authenticateUser(AuthenticateController.java:51) ~[classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_172]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_172]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_172]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_172]
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.32.jar:8.5.32]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.32.jar:8.5.32]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:114) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at com.bharti.firstspringbootproject.security.JwtAuthenticationFilter.doFilterInternal(JwtAuthenticationFilter.java:49) ~[classes/:na]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177) ~[spring-security-web-4.2.7.RELEASE.jar:4.2.7.RELEASE]
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:347) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:263) ~[spring-web-4.3.18.RELEASE.jar:4.3.18.RELEASE]
    at 

Answer 1

The JavaMail FAQ has instructions for configuring JavaMail to use a proxy server . If you're using JavaMail 1.6.0 or later, set the mail.smtp.proxy.host and mail.smtp.proxy.port properties.

Answer 2

To clarify at least one point concerning the usage of https.proxySet=true and http.proxySet=true.

JDK-4632974 proxySet=false is ignored for HttpURLConnection.getOutputStream

"The use of property http.proxySet was eliminated in favor of simply testing for the presence of the http.proxyHost property. This property existed up to JDK1.0.2 but was removed for JDK1.1 in 1996."

In other words, do not use proxySet as it serves no purpose. It is non-existing Java system property nowadays.

Answer 3

I already wrote the mail server using spring boot. but I didn't get this kind of issue. This seems network(proxy) issue. Please try without proxy.

Find below sample code for your reference.

@Autowired
private JavaMailSender javaMailSender;

I used MineMessage as below.

   MimeMessage message = javaMailSender.createMimeMessage();
   MimeMessageHelper helper = new MimeMessageHelper(message);
   helper.setFrom(systemEmail);
   helper.setTo(mailBacklog.getToAddress());
     if(mailBacklog.getSubject() != null) {
          helper.setSubject(mailBacklog.getSubject());
     }
   helper.setText(mailBacklog.getMessage());
   javaMailSender.send(message);

sample configuration (.yml)

spring:  
  mail:
    host: smtp.gmail.com
    port: 587
    username: xxxxxxxx@gmail.com
    password: xxxxxx
    properties:
      mail:
        smtp:
          auth: true
          starttls:
            enable: true