Spring Boot – How to send email via SMTP
Tags: spring, springboot
Published: 2022-07-19 04:13:57

## Project Directory
![](https://i.imgur.com/9BEgsy1.png)
## Maven
To send email, declares **spring-boot-starter-mail**, it will pull the JavaMail dependencies.
+ pom.xml
```xml
<?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>2.7.1</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.example</groupId>
	<artifactId>spring-boot-send-email</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>spring-boot-send-email</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-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<scope>runtime</scope>
			<optional>true</optional>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-configuration-processor</artifactId>
			<optional>true</optional>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<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>
```
Display the project dependencies.

```
mvn dependency:tree
[INFO] Scanning for projects...
[INFO] 
[INFO] -----------------< com.example:spring-boot-send-email >-----------------
[INFO] Building spring-boot-send-email 0.0.1-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] --- maven-dependency-plugin:3.3.0:tree (default-cli) @ spring-boot-send-email ---
[INFO] com.example:spring-boot-send-email:jar:0.0.1-SNAPSHOT
[INFO] +- org.springframework.boot:spring-boot-starter-web:jar:2.7.1:compile
[INFO] |  +- org.springframework.boot:spring-boot-starter:jar:2.7.1:compile
[INFO] |  |  +- org.springframework.boot:spring-boot-starter-logging:jar:2.7.1:compile
[INFO] |  |  |  +- ch.qos.logback:logback-classic:jar:1.2.11:compile
[INFO] |  |  |  |  \- ch.qos.logback:logback-core:jar:1.2.11:compile
[INFO] |  |  |  +- org.apache.logging.log4j:log4j-to-slf4j:jar:2.17.2:compile
[INFO] |  |  |  |  \- org.apache.logging.log4j:log4j-api:jar:2.17.2:compile
[INFO] |  |  |  \- org.slf4j:jul-to-slf4j:jar:1.7.36:compile
[INFO] |  |  +- jakarta.annotation:jakarta.annotation-api:jar:1.3.5:compile
[INFO] |  |  \- org.yaml:snakeyaml:jar:1.30:compile
[INFO] |  +- org.springframework.boot:spring-boot-starter-json:jar:2.7.1:compile
[INFO] |  |  +- com.fasterxml.jackson.core:jackson-databind:jar:2.13.3:compile
[INFO] |  |  |  +- com.fasterxml.jackson.core:jackson-annotations:jar:2.13.3:compile
[INFO] |  |  |  \- com.fasterxml.jackson.core:jackson-core:jar:2.13.3:compile
[INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jdk8:jar:2.13.3:compile
[INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jsr310:jar:2.13.3:compile
[INFO] |  |  \- com.fasterxml.jackson.module:jackson-module-parameter-names:jar:2.13.3:compile
[INFO] |  +- org.springframework.boot:spring-boot-starter-tomcat:jar:2.7.1:compile
[INFO] |  |  +- org.apache.tomcat.embed:tomcat-embed-core:jar:9.0.64:compile
[INFO] |  |  +- org.apache.tomcat.embed:tomcat-embed-el:jar:9.0.64:compile
[INFO] |  |  \- org.apache.tomcat.embed:tomcat-embed-websocket:jar:9.0.64:compile
[INFO] |  +- org.springframework:spring-web:jar:5.3.21:compile
[INFO] |  |  \- org.springframework:spring-beans:jar:5.3.21:compile
[INFO] |  \- org.springframework:spring-webmvc:jar:5.3.21:compile
[INFO] |     +- org.springframework:spring-aop:jar:5.3.21:compile
[INFO] |     +- org.springframework:spring-context:jar:5.3.21:compile
[INFO] |     \- org.springframework:spring-expression:jar:5.3.21:compile
[INFO] +- org.springframework.boot:spring-boot-devtools:jar:2.7.1:runtime
[INFO] |  +- org.springframework.boot:spring-boot:jar:2.7.1:compile
[INFO] |  \- org.springframework.boot:spring-boot-autoconfigure:jar:2.7.1:compile
[INFO] +- org.springframework.boot:spring-boot-configuration-processor:jar:2.7.1:compile
[INFO] +- org.springframework.boot:spring-boot-starter-test:jar:2.7.1:test
[INFO] |  +- org.springframework.boot:spring-boot-test:jar:2.7.1:test
[INFO] |  +- org.springframework.boot:spring-boot-test-autoconfigure:jar:2.7.1:test
[INFO] |  +- com.jayway.jsonpath:json-path:jar:2.7.0:test
[INFO] |  |  +- net.minidev:json-smart:jar:2.4.8:test
[INFO] |  |  |  \- net.minidev:accessors-smart:jar:2.4.8:test
[INFO] |  |  |     \- org.ow2.asm:asm:jar:9.1:test
[INFO] |  |  \- org.slf4j:slf4j-api:jar:1.7.36:compile
[INFO] |  +- jakarta.xml.bind:jakarta.xml.bind-api:jar:2.3.3:test
[INFO] |  |  \- jakarta.activation:jakarta.activation-api:jar:1.2.2:test
[INFO] |  +- org.assertj:assertj-core:jar:3.22.0:test
[INFO] |  +- org.hamcrest:hamcrest:jar:2.2:test
[INFO] |  +- org.junit.jupiter:junit-jupiter:jar:5.8.2:test
[INFO] |  |  +- org.junit.jupiter:junit-jupiter-api:jar:5.8.2:test
[INFO] |  |  |  +- org.opentest4j:opentest4j:jar:1.2.0:test
[INFO] |  |  |  +- org.junit.platform:junit-platform-commons:jar:1.8.2:test
[INFO] |  |  |  \- org.apiguardian:apiguardian-api:jar:1.1.2:test
[INFO] |  |  +- org.junit.jupiter:junit-jupiter-params:jar:5.8.2:test
[INFO] |  |  \- org.junit.jupiter:junit-jupiter-engine:jar:5.8.2:test
[INFO] |  |     \- org.junit.platform:junit-platform-engine:jar:1.8.2:test
[INFO] |  +- org.mockito:mockito-core:jar:4.5.1:test
[INFO] |  |  +- net.bytebuddy:byte-buddy:jar:1.12.11:test
[INFO] |  |  +- net.bytebuddy:byte-buddy-agent:jar:1.12.11:test
[INFO] |  |  \- org.objenesis:objenesis:jar:3.2:test
[INFO] |  +- org.mockito:mockito-junit-jupiter:jar:4.5.1:test
[INFO] |  +- org.skyscreamer:jsonassert:jar:1.5.0:test
[INFO] |  |  \- com.vaadin.external.google:android-json:jar:0.0.20131108.vaadin1:test
[INFO] |  +- org.springframework:spring-core:jar:5.3.21:compile
[INFO] |  |  \- org.springframework:spring-jcl:jar:5.3.21:compile
[INFO] |  +- org.springframework:spring-test:jar:5.3.21:test
[INFO] |  \- org.xmlunit:xmlunit-core:jar:2.9.0:test
[INFO] \- org.springframework.boot:spring-boot-starter-mail:jar:2.7.1:compile
[INFO]    +- org.springframework:spring-context-support:jar:5.3.21:compile
[INFO]    \- com.sun.mail:jakarta.mail:jar:1.6.7:compile
[INFO]       \- com.sun.activation:jakarta.activation:jar:1.2.2:compile
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  2.153 s
[INFO] Finished at: 2022-07-18T14:40:39+07:00
[INFO] ------------------------------------------------------------------------
```
## Gmail SMTP
This example is using Gmail SMTP server, tested with TLS (port 587) and SSL (port 465). Read this [Gmail SMTP](https://support.google.com/mail/answer/7126229)
+ application.properties
![](https://i.imgur.com/Wqb4YH1.png)

### Note

For Gmail SMTP, if your account is enabled the 2-Step verification, please create an **App Password**
+ Access link: [https://support.google.com/accounts/answer/185833?p=InvalidSecondFactor](https://support.google.com/accounts/answer/185833?p=InvalidSecondFactor)
![](https://i.imgur.com/EXGzhoP.png)
+ URL : [https://myaccount.google.com/security](https://myaccount.google.com/security)
![](https://i.imgur.com/LZrfWle.png)
![](https://i.imgur.com/eRJWPKs.png)
![](https://i.imgur.com/fjDMfAO.jpg)
Puts the newly generated app password into **spring.mail.password**.
![](https://i.imgur.com/8qLVNcc.png)

### Sending Email
Spring provides an **JavaMailSender** interface on top of [JavaMail APIs](https://javaee.github.io/javamail/).
+ Send a normal text email
![](https://i.imgur.com/wSlwnHF.png)
+ Send an HTML email and a file attachment.
![](https://i.imgur.com/zqUCrP5.png)

### Demo

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

```java
package com.example.sendemail;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.core.io.ClassPathResource;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;

import javax.mail.MessagingException;
import javax.mail.internet.MimeMessage;
import java.io.IOException;

@SpringBootApplication
public class SpringBootSendEmailApplication implements CommandLineRunner {
	@Autowired
	private JavaMailSender javaMailSender;
	public static void main(String[] args) {
		SpringApplication.run(SpringBootSendEmailApplication.class, args);
	}

	@Override
	public void run(String... args) throws Exception {
		System.out.println("Sending Email...");
		sendEmail();
		System.out.println("Done");
	}

	void sendEmailWithAttachment() throws MessagingException, IOException {
		MimeMessage msg = javaMailSender.createMimeMessage();
		MimeMessageHelper helper = new MimeMessageHelper(msg, true);
		helper.setTo("hauntps@gmail.com");
		helper.setSubject("Testing from Spring Boot");
		helper.setText("<h1>Check attachment for image!</h1>", true);
		helper.addAttachment("my_photo.png", new ClassPathResource("android.png"));
		javaMailSender.send(msg);

	}
	void sendEmail() {
		SimpleMailMessage msg = new SimpleMailMessage();
		msg.setTo("hauntps@gmail.com", "ngocnt@gmail.com");
		msg.setSubject("Testing from Spring Boot");
		msg.setText("Hello World \n Spring Boot Email");
		javaMailSender.send(msg);
	}

}
```
![](https://i.imgur.com/EuDpUa4.png)
![](https://i.imgur.com/MgBA6Zu.png)
## Source code
https://github.com/java-cake/spring-boot/tree/main/spring-boot-send-email