Spring Boot Starters

Spring Boot provides many starters that allow us to add dependencies (jars) in the classpath. Spring Boot built-in starters make development easier and rapid. Spring Boot Starters are the dependency descriptors.

If you have any prior experience of working with Spring MVC, you will be knowing how tedious it is configuring the dependencies for your project.

Spring Boot starters are built to address this issue. Find out more reasons for using it here. You include a starter for web and every jar that you require for web will be added to your classpath.

What is a Spring Boot Starter?

Spring Boot starters are templates that contain a collection of all the relevant transitive dependencies that are needed to start a particular functionality.

Here is an example of dependencies you will have to add in pom.xml in the traditional Spring project to implement Spring security:

<!-- spring security -->
<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-web</artifactId>
    <version>${spring.security.version}</version>
</dependency>

<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-config</artifactId>
    <version>${spring.security.version}</version>
</dependency>

<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-taglibs</artifactId>
    <version>${spring.security.version}</version>
</dependency>

The same thing can be achieved in Spring Boot by adding a single starter (as shown below).

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

In the Spring Boot Framework, all the starters follow a similar naming pattern: spring-boot-starter-*, where * denotes a particular type of application. For example, if we want to use Spring and JPA for database access, we need to include the spring-boot-starter-data-jpa dependency in our pom.xml file of the project.

Commonly used starters

Name	Description
spring-boot-starter-thymeleaf	It is used to build MVC web applications using Thymeleaf views.
spring-boot-starter-web-services	It is used for Spring Web Services.
spring-boot-starter-mail	It is used to support Java Mail and Spring Framework’s email sending.
spring-boot-starter-data-redis	It is used for Redis key-value data store with Spring Data Redis and the Jedis client.
spring-boot-starter-web	It is used for building the web application, including RESTful applications using Spring MVC. It uses Tomcat as the default embedded container.
spring-boot-starter-test	It is used to test Spring Boot applications with libraries, including JUnit, Hamcrest, and Mockito.
spring-boot-starter-jdbc	It is used for JDBC with the Tomcat JDBC connection pool.
spring-boot-starter-security	It is used for Spring Security.
spring-boot-starter-log4j2	It is used for Log4j2 for logging. An alternative to spring-boot-starter-logging.
spring-boot-starter-logging	It is used for logging using Logback. Default logging starter.

Commonly used Spring Boot Starters

Adding starters to your project

The simplest way to add a starter to your project is by adding dependencies while initializing the project using Spring Initializr. When you click on the Add Dependencies(indicated in the screenshot given below) button, you get a list of starters from which you can select.

The other way is to add <dependency> tags inside <dependencies> tag in pom.xml.

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