Send Email Using Spring Boot

Hello everyone, today we will learn how to send an email via SMTP in Spring Boot.

Technologies used: 

• Spring Boot 2.1.1.RELEASE 
• Java Mail 1.6.2
• Maven 3 
• Java 8

Project Structure:

Dependency Managemen(pom.xml):

spring-boot-starter-mail will pull the JavaMail dependencies.

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
               https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.1.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.knf.sibin.dev.emaildemo</groupId>
    <artifactId>emailDemo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>emailDemo</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

Spring Boot Mail Server Properties

Once the dependency is in place, the next step is to specify the mail server properties in the application.properties file using the spring.mail.* namespace.

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

Sending Email

Spring provides a JavaMailSender interface on top of JavaMail APIs.

package com.knf.sibin.dev.emaildemo.util;
import java.io.IOException;
import javax.mail.MessagingException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.stereotype.Component;
@Component
public class EmailUtil {
    @Autowired
    private JavaMailSender javaMailSender;
    private static final Logger LOG = LoggerFactory.getLogger(EmailUtil.class);
    public void sendEmail() throws MessagingException, IOException {
        LOG.info("Ready to sent an email");
        SimpleMailMessage msg = new SimpleMailMessage();
        msg.setTo("knowledgefactory333@gmail.com");
        msg.setSubject("Test Mail");
        msg.setText("Greetings from Spring Boot Email");
        javaMailSender.send(msg);
        LOG.info("Successfully dropped an email");
    }
}

Main class

Start Spring Boot, and it will send out an email.

package com.knf.sibin.dev.emaildemo;

import java.io.IOException;
import javax.mail.MessagingException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import com.knf.sibin.dev.emaildemo.util.EmailUtil;

@SpringBootApplication
public class EmailDemoApplication implements CommandLineRunner {
    @Autowired
    private EmailUtil emailUtil;

    public static void main(String[] args) {
        SpringApplication.run(EmailDemoApplication.class, args);
    }

    @Override
    public void run(String... args) {
        try {
            emailUtil.sendEmail();
        } catch (MessagingException | IOException e) {
            e.printStackTrace();
        }
    }
}

Local Setup:

Step 1: Download or clone the source code to a local machine.

Step 2: mvn clean install

Step 3: Run the Spring Boot application

mvn spring-boot:run

Terminal

. ____ _ __ _ _

/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \

( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \

\\/ ___)| |_)| | | | | || (_| | ) ) ) )

' |____| .__|_| |_|_| |_\__, | / / / /

=========|_|==============|___/=/_/_/_/

 Ready to sent an email

 Successfully dropped an email

Download Source Code

https://github.com/knowledgefactory4u/KnowledgeFactory