Spring Boot で簡単に Gmail からメールを送る方法

Spring Boot のライブラリ Spring Mail を使って Gmailからメールが送付できました。Spring Mailの扱い方さえ分かれば簡単でしたので、まとめます。今回確認したのは、任意かつ複数の宛先(To, Cc, Bcc)に対してメールを送付する方法です。

pom.xml

まずはSpring Mail ライブラリを取得します。おなじみのMavenで取得します。次の dependency を追加します。

pom.xml – 一部抜粋
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-mail</artifactId>
</dependency>

次にMail送付の実行処理を書いていきます。

MailController.java

今回はControllerクラスに処理を書きました。画面から次のメソッドにアクセスされたら任意の宛先へメールを送付します。

MailController.java
package com.example.app;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.mail.MailSender;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
public class MailController {

  public static final String LINE_SEPARATOR = System.getProperty("line.separator");

  @Autowired
  private MailSender mailSender;

  @RequestMapping(value = "/", method = RequestMethod.GET)
  public String index() {
    return "index";
  }

  @RequestMapping(value = "/", method = RequestMethod.POST)
  public String sendMail() {

      SimpleMailMessage msg = new SimpleMailMessage();
      msg.setTo(".................@gmail.com");// To
      msg.setBcc("................@yahoo.co.jp");// Bcc
      msg.setCc(new String[] { "................@gmail.com", "................@gmail.com" });// Cc Multiple Case

      String insertMessage = "Test from Spring Mail" + LINE_SEPARATOR;
      insertMessage += "Test from Spring Mail" + LINE_SEPARATOR;

      msg.setSubject("Test from Spring Mail");// Set Title
      msg.setText(insertMessage);// Set Message
      mailSender.send(msg);

    return "index";
  }

}

最後は設定です。

application.properties

これもお馴染み application.properties に設定を書きます。

application.properties
spring.mail.host=smtp.gmail.com
spring.mail.port=587
spring.mail.username=.................@gmail.com
spring.mail.password=**************
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true

注意事項

Gmailでメール送付する場合、application.properties に記述するパスワードはGmailにログインするときのパスワードではありません。プログラムからメール送付する用のパスワードを生成して、application.properties に書き込みます。

補足

存在しないメールアドレスを送信元(spring.mail.username)に設定したらどうなるのか、試してみました。

結果、エラーになってメール送信することが出来ませんでした。エラー文は次のとおりです。

eclipseでのエラー
javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted. Learn more at
535 5.7.8  https://support.google.com/mail/?p=BadCredentials n140sm90732178pfd.132 - gsmtp

  at com.sun.mail.smtp.SMTPTransport$Authenticator.authenticate(SMTPTransport.java:965) ~[javax.mail-1.6.2.jar:1.6.2]
  at com.sun.mail.smtp.SMTPTransport.authenticate(SMTPTransport.java:876) ~[javax.mail-1.6.2.jar:1.6.2]
  at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:780) ~[javax.mail-1.6.2.jar:1.6.2]
  at javax.mail.Service.connect(Service.java:366) ~[javax.mail-1.6.2.jar:1.6.2]
  at org.springframework.mail.javamail.JavaMailSenderImpl.connectTransport(JavaMailSenderImpl.java:515) ~[spring-context-support-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:435) ~[spring-context-support-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:321) ~[spring-context-support-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:310) ~[spring-context-support-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at com.example.app.MailController.sendMail(MailController.java:36) ~[classes/:na]
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_201]
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_201]
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_201]
  at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_201]
  at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:215) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:142) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:998) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:901) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:875) ~[spring-webmvc-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.1.2.RELEASE.jar:5.1.2.RELEASE]
  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:770) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_201]
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_201]
  at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.12.jar:9.0.12]
  at java.lang.Thread.run(Thread.java:748) [na:1.8.0_201]

Sprring Boot のWhitelabel Error Page

Whitelabel Error Page
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.

Wed Aug 07 14:09:55 JST 2019
There was an unexpected error (type=Internal Server Error, status=500).
Authentication failed; nested exception is javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted. Learn more at 535 5.7.8 https://support.google.com/mail/?p=BadCredentials n140sm90732178pfd.132 - gsmtp
org.springframework.mail.MailAuthenticationException: Authentication failed; nested exception is javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted. Learn more at 535 5.7.8 https://support.google.com/mail/?p=BadCredentials n140sm90732178pfd.132 - gsmtp at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:438) at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:321) at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:310) at com.example.app.MailController.sendMail(MailController.java:36) 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 org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:215) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:142) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:998) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:901) at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:875) at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:770) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748) Caused by: javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted. Learn more at 535 5.7.8 https://support.google.com/mail/?p=BadCredentials n140sm90732178pfd.132 - gsmtp at com.sun.mail.smtp.SMTPTransport$Authenticator.authenticate(SMTPTransport.java:965) at com.sun.mail.smtp.SMTPTransport.authenticate(SMTPTransport.java:876) at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:780) at javax.mail.Service.connect(Service.java:366) at org.springframework.mail.javamail.JavaMailSenderImpl.connectTransport(JavaMailSenderImpl.java:515) at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:435) ... 57 more

以上、Spring Boot で簡単に Gmail を送る方法でした。