SpringBoot – 發送帶有附件的電子郵件 · HowToDoInJava 中文系列教程

# SpringBoot – 發送帶有附件的電子郵件 > 原文： [https://howtodoinjava.com/spring-boot2/send-email-with-attachment/](https://howtodoinjava.com/spring-boot2/send-email-with-attachment/) 了解如何借助[`JavaMailSender`](https://howtodoinjava.com/spring-core/send-email-with-spring-javamailsenderimpl-example/)在 spring boot 應用程序中發送電子郵件，以發送簡單電子郵件以及帶有附件的電子郵件。 ## 1\. Maven 在 Spring Boot 應用程序中，包括`spring-boot-starter-mail`依賴項。 `pom.xml` ```java <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.8.RELEASE</version> </parent> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-mail</artifactId> </dependency> </dependencies> ``` ## 2\. SMTP 配置使用 spring boot，我們可以在`application.properties`文件中配置 SMTP 設置。 #### 2.1. 郵箱 `application.properties` ```java debug=true spring.mail.host=smtp.gmail.com spring.mail.port=25 spring.mail.username=admin@gmail.com spring.mail.password=xxxxxx # Other properties spring.mail.properties.mail.debug=true spring.mail.properties.mail.transport.protocol=smtp spring.mail.properties.mail.smtp.auth=true spring.mail.properties.mail.smtp.connectiontimeout=5000 spring.mail.properties.mail.smtp.timeout=5000 spring.mail.properties.mail.smtp.writetimeout=5000 # TLS , port 587 spring.mail.properties.mail.smtp.starttls.enable=true # SSL, post 465 #spring.mail.properties.mail.smtp.socketFactory.port = 465 #spring.mail.properties.mail.smtp.socketFactory.class = javax.net.ssl.SSLSocketFactory ``` > 為了能夠使用兩因素身份驗證并關閉“允許不太安全的應用程序”選項，強烈建議使用應用程序密碼代替 Gmail 密碼。 > > 請參閱：[https://support.google.com/accounts/answer/185833](https://support.google.com/accounts/answer/185833) 如果您可以訪問下面的 SMTP 服務器，請在下面自由使用。 #### 2.2. Outlook 如果它是某些公司服務器，請從管理員那里查找此信息。 `Outlook Configuration` ```java spring.mail.host=smtp-mail.outlook.com spring.mail.port=587 spring.mail.username=outlookuserid@outlook.com spring.mail.password=xxxxxx spring.mail.properties.mail.protocol=smtp spring.mail.properties.mail.tls=true spring.mail.properties.mail.smtp.auth=true spring.mail.properties.mail.smtp.starttls.enable=true spring.mail.properties.mail.smtp.ssl.trust=smtp-mail.outlook.com ``` #### 2.3. AWS SES 從您的 AWS 設置頁面中找到相關配置。[閱讀更多](https://docs.aws.amazon.com/ses/latest/DeveloperGuide/sending-email.html)。 `AWS SES Configuration` ```java spring.mail.host=email-smtp.us-east-1.amazonaws.com spring.mail.port=465 spring.mail.username=xxxxxxxxxxx spring.mail.password=xxxxxxxxxxx spring.mail.properties.mail.smtp.starttls.enable=true spring.mail.properties.mail.smtp.starttls.required=true spring.mail.properties.mail.smtp.ssl.enavle=true spring.mail.properties.mail.protocol=smtps spring.mail.properties.mail.smtps.auth=true ``` ## 3\. 預先配置的電子郵件模板我們可以創建電子郵件模板以供每次重用 – 我們必須定期或在任何特定事件或持續時間內發送電子郵件。在給定的示例中，我們正在使用[`SimpleMailMessage`](https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/mail/SimpleMailMessage.html)創建一個非常簡單的純文本電子郵件。 `EmailConfig.java` ```java import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.mail.SimpleMailMessage; @Configuration public class EmailConfig { @Bean public SimpleMailMessage emailTemplate() { SimpleMailMessage message = new SimpleMailMessage(); message.setTo("user@gmail.com"); message.setFrom("admin@gmail.com"); message.setSubject("Important email"); message.setText("FATAL - Application crash. Save your job !!"); return message; } } ``` ## 4\. 發送簡單的電子郵件為了發送不同類型的電子郵件，我們創建了一個`EmailService`類，該類可以采用在發送電子郵件之前在電子郵件中設置所需的參數。 `EmailService.java` ```java @Service("emailService") public class EmailService { @Autowired private JavaMailSender mailSender; @Autowired private SimpleMailMessage preConfiguredMessage; /** * This method will send compose and send the message * */ public void sendMail(String to, String subject, String body) { SimpleMailMessage message = new SimpleMailMessage(); message.setTo(to); message.setSubject(subject); message.setText(body); mailSender.send(message); } /** * This method will send a pre-configured message * */ public void sendPreConfiguredMail(String message) { SimpleMailMessage mailMessage = new SimpleMailMessage(preConfiguredMessage); mailMessage.setText(message); mailSender.send(mailMessage); } } ``` ## 5\. 發送帶有附件的電子郵件使用[`MimeMessageHelper`](https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/mail/javamail/MimeMessageHelper.html)發送多媒體電子郵件，該電子郵件用于配置[`MimeMessage`](https://docs.oracle.com/javaee/7/api/javax/mail/internet/MimeMessage.html)。這些 mime 消息是富文本電子郵件。 `Email with attachment` ```java @Autowired private JavaMailSender mailSender; public void sendMailWithAttachment(String to, String subject, String body, String fileToAttach) { MimeMessagePreparator preparator = new MimeMessagePreparator() { public void prepare(MimeMessage mimeMessage) throws Exception { mimeMessage.setRecipient(Message.RecipientType.TO, new InternetAddress(to)); mimeMessage.setFrom(new InternetAddress("admin@gmail.com")); mimeMessage.setSubject(subject); mimeMessage.setText(body); FileSystemResource file = new FileSystemResource(new File(fileToAttach)); MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, true); helper.addAttachment("logo.jpg", file); } }; try { mailSender.send(preparator); } catch (MailException ex) { // simply log it and go on... System.err.println(ex.getMessage()); } } ``` ## 6\. 發送帶有內嵌圖像的電子郵件富文本格式包括介于文本內容之間的媒體內容。為此，我們必須使用`MimeMessageHelper`的`addInline()`方法。 `Email with inline images` ```java @Autowired private JavaMailSender mailSender; public void sendMailWithInlineResources(String to, String subject, String fileToAttach) { MimeMessagePreparator preparator = new MimeMessagePreparator() { public void prepare(MimeMessage mimeMessage) throws Exception { mimeMessage.setRecipient(Message.RecipientType.TO, new InternetAddress(to)); mimeMessage.setFrom(new InternetAddress("admin@gmail.com")); mimeMessage.setSubject(subject); MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, true); helper.setText("<html><body><img src='cid:identifier1234'></body></html>", true); FileSystemResource res = new FileSystemResource(new File(fileToAttach)); helper.addInline("identifier1234", res); } }; try { mailSender.send(preparator); } catch (MailException ex) { // simply log it and go on... System.err.println(ex.getMessage()); } } ``` ## 7\. Spring Boot 發送電子郵件演示要使用上述配置發送電子郵件，請更新`application.properties`文件中的`spring.mail.username`和`spring.mail.password`屬性。現在執行`EmailService`的方法發送電子郵件。 `Application.java` ```java import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.CommandLineRunner; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class Application implements CommandLineRunner { @Autowired private EmailService emailService; public static void main(String[] args) { SpringApplication.run(Application.class, args); } @Override public void run(String... args) { emailService.sendMail("lokeshgupta1981@gmail.com", "Hi", "Ho ho ho"); emailService.sendPreConfiguredMail("Ho ho ho"); } } ``` 請給我發送有關**通過 SpringBoot**發送電子郵件的問題。學習愉快！ [下載源碼](https://github.com/lokeshgupta1981/SpringExamples/tree/master/email)