Spring boot – Send email with attachment

Learn how to send email in spring boot applications with the help of JavaMailSender for sending simple emails as well as emails with attachments.

1. Maven

In Spring boot application, include spring-boot-starter-mail dependency. Use the appropriate spring boot version.

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>${spring-boot-version}</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 Configuration

With spring boot, we can configure SMTP settings in application.properties file.

2.1. Gmail

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

To be able to use two factor authentication as well as keep the “allow less secure apps” option off, it is highly recommended to use an app password instead of the Gmail password.

Refer: https://support.google.com/accounts/answer/185833

Feel free to use the below SMTP servers, in case you have access to them.

2.2. Outlook

Find this information from your admin in case it is some corporate server.

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

Find relevant configuration from your AWS settings page. [Read More]

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. Pre-configured Email Templates

We can create email templates to reuse every time – we have to send an email periodically or on any specific event or duration. In the given example, we are creating a straightforward text-only email using SimpleMailMessage.

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. Sending Plain-text Simple Email

To send emails of different types, we have created an EmailService class that can take the required parameters to set in emails before sending them.

@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. Sending Email with Attachment

Multimedia emails are sent using MimeMessageHelper which is used to configure MimeMessage. These mime messages are rich text emails.

@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. Sending Email with Inline Images

The rich text includes media content in between text content. To do so in emails, we have to use MimeMessageHelper‘s addInline() method.

@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 Send Email Demo

To send emails using the above configuration, please update the spring.mail.username and spring.mail.password properties in application.properties file.

Now execute EmailService‘s method to send emails.

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("some-email-address@gmail.com", "Happy Coding", "Email sent with demo application");
         
        emailService.sendPreConfiguredMail("Happy Coding");
    }
}

Drop me your questions related to sending emails with spring boot.

Happy Learning !!