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Spring Boot Email Sending Tutorial and Code Examples

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Written by Nam Ha Minh

Last Updated on 25 July 2022 &nbsp | &nbsp

1. Declare Dependency for Spring Boot Mail

Spring Boot Starter Mail is a thin wrapper around Jakarta Mail (the new name of JavaMail), which makes it easier to integrate emailing functionality into Spring-based applications. So declare the following dependency in the Maven project file:

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-mail</artifactId>
</dependency>

2. Configure Mail Properties

In order to send email from your application, you need to configure SMTP server settings in the Spring Boot application configuration file (

application.properties

) as follows:

spring.mail.host=smtp.gmail.com
spring.mail.port=587
spring.mail.username=your_email_address
spring.mail.password=your_email_password
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true

This is the configuration for using GMail’s SMTP server with connection encrypted (using TLS). Of course you can use settings of your own SMTP server. In case you use GMail, you must enable SMTP in your GMail account settings and generate an access password (not your email password) for better security.

3. Configure a JavaMailSender

Spring Mail provides

JavaMailSender

which is the key interface that defines common methods for sending emails. After configuring mail properties in the

application.properties

file, you can tell Spring framework to inject the default implementation of

JavaMailSender

into a Spring MVC controller class like this:

@Controller
public class AppController {

	@Autowired
	private JavaMailSender mailSender;
	
	public void sendEmail() {
		// use mailSender here...
	}	
}

Also in a business/service class:

@Service
public class BusinessService {
	
	@Autowired
	private JavaMailSender mailSender;
	
	public void sendEmail() {
		// use mailSender here...
	}
}

Or in any Spring-managed component as follows:

@Component
public class BusinessComponent {

	@Autowired
	private JavaMailSender mailSender;
	
	public void sendEmail() {
		// use mailSender here...
	}
}

In a non-Spring environment (e.g. in a JUnit test), you must create a new instance of

JavaMailSenderImpl

– the default implementation of

JavaMailSender

like this:

JavaMailSenderImpl mailSender = new JavaMailSenderImpl();
mailSender.setHost("smtp.gmail.com");
mailSender.setPort(587);
mailSender.setUsername("your_email");
mailSender.setPassword("your_password");

Properties properties = new Properties();
properties.setProperty("mail.smtp.auth", "true");
properties.setProperty("mail.smtp.starttls.enable", "true");

mailSender.setJavaMailProperties(properties);

So you can see, in a Spring Boot application, you just need to declare the mail properties and then you’re ready to use the

JavaMailSender

4. Code Example for Sending Simple Email (Plain Text)

The code snippet below demonstrates how to send a plain text email:

String from = "[email protected]";
String to = "[email protected]";

SimpleMailMessage message = new SimpleMailMessage();

message.setFrom(from);
message.setTo(to);
message.setSubject("This is a plain text email");
message.setText("Hello guys! This is a plain text email.");

mailSender.send(message);

You see, the code is simple and self-explanatory. The

send()

method may throw

MailException

which is a runtime exception in case of error – so you can decide to catch this exception or not. And this is how the email looks like in GMail: text email content

5. Code Example for Sending HTML Email

And the following code example shows you how to send an email in HTML format:

String from = "[email protected]";
String to = "[email protected]";

MimeMessage message = mailSender.createMimeMessage();
MimeMessageHelper helper = new MimeMessageHelper(message);

helper.setSubject("This is an HTML email");
helper.setFrom(from);
helper.setTo(to);

boolean html = true;
helper.setText("<b>Hey guys</b>,<br><i>Welcome to my new home</i>", html);

mailSender.send(message);

You see, you can embed HTML tags directly into the body text of the email message. And below is how the email looks like in GMail: html email content

6. Code Example for Sending Email with Attachment

It’s also simple to send an HTML with an attachment, as shown in the code example below:

String from = "[email protected]";
String to = "[email protected]";
	
MimeMessage message = mailSender.createMimeMessage();
MimeMessageHelper helper = new MimeMessageHelper(message, true);

helper.setSubject("Here's your e-book");
helper.setFrom(from);
helper.setTo(to);

helper.setText("<b>Dear friend</b>,<br><i>Please find the book attached.</i>", true);

FileSystemResource file = new FileSystemResource(new File("Book.pdf"));
helper.addAttachment("FreelanceSuccess.pdf", file);

mailSender.send(message);

As you can see, the code reads a PDF file from file system and attach it into the outgoing email. Below is how the email looks like in GMail: email with attachment

7. Code Example for Sending Email with Inline Images

You can also inline a picture right inside the email content, as shown in the following code example:

String from = "[email protected]";
String to = "[email protected]";
	
MimeMessage message = mailSender.createMimeMessage();
MimeMessageHelper helper = new MimeMessageHelper(message, true);

helper.setSubject("Here's your pic");
helper.setFrom(from);
helper.setTo(to);

String content = "<b>Dear guru</b>,<br><i>Please look at this nice picture:.</i>"
		+ "<br><img src='cid:image001'/><br><b>Best Regards</b>"; 
helper.setText(content, true);

FileSystemResource resource = new FileSystemResource(new File("picture.png"));
helper.addInline("image001", resource);

mailSender.send(message);

Note that you must specify cid value for the image tag, where a picture will be embedded to. And here’s how the email looks like in GMail: inline image email Those are common code examples for sending emails in a Spring Boot application. I hope you’ve found this article helpful. To see the coding in action, I recommend you to watch the following video:

You can also download the sample project in the Attachments section below, or

About the Author:

Nam Ha Minh is certified Java programmer (SCJP and SCWCD). He started programming with Java in the time of Java 1.4 and has been falling in love with Java since then. Make friend with him on

is certified Java programmer (SCJP and SCWCD). He started programming with Java in the time of Java 1.4 and has been falling in love with Java since then. Make friend with him on Facebook and watch his Java videos you YouTube.

Attachments:SpringBootEmailExamples.zip[Sample Spring Boot project]68 kB