Spring Framework and Spring Boot are both tools for Java development in the larger Spring family. However, they each have their roles and specific features. In this article, we’ll take a look at Spring vs Spring Boot, pointing out what makes each unique.
1. Introduction – Purpose and Scope
1.1 Spring Framework
Spring Framework, developed by Pivotal Software, is a comprehensive and modular framework for Java development. One of the key features of the Spring Framework is its support for design patterns like Dependency Injection and Inversion of Control.
Dependency Injection is like letting different parts of a program work together without one part knowing too much about the others. It helps make pieces of the program more separate and useful on their own.
Inversion of Control is when the framework manages how all these pieces fit together. Instead of developers having to control every detail, the framework handles how things connect and work, making it easier to build flexible and organized software.
1.2 Spring Boot
Spring Boot, on the other hand, is an extension of the Spring Framework designed to make it even easier to create applications that are ready for use in the real world. Spring boot provides a convention-over-configuration approach, meaning that it comes with sensible defaults and reduces the need for manual setup and configuration.
The main goal of Spring Boot is to streamline the development of applications, making it easier for developers to create robust, scalable, and easily deployable systems.
2. Dependency Management
To begin, let’s check out the fundamental Maven dependencies needed for a basic web application with Spring and Spring Boot.
2.1 Maven Essentials for a Spring Web Application
Developers need to explicitly manage dependencies by including the necessary JAR files in the project. Here’s a snippet of a typical Maven dependency needed for a web application in a Spring project.
2.1.1 spring-web
The spring-web module is foundational for web development with Spring. It provides essential features for handling web-related components and managing HTTP requests.
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
2.1.2 spring-webmvc
For building web applications using the Model-View-Controller (MVC) pattern, the spring-webmvc module is indispensable. It includes components like dispatcher servlets, controllers, and view resolvers.
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
2.2 Maven Dependencies for Spring Boot
Only a single dependency is needed to initiate a web application with Spring Boot.
2.2.1 spring-boot-starter-web
The spring-boot-starter-web dependency includes everything needed to set up a basic web application, including an embedded web server. Spring Boot starters package together commonly used dependencies, making it easy for us to add them to our project by entering just one line in the project settings.
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>${spring-boot.version}</version>
</dependency>
</dependencies>
3. Microservices Support
3.1 Microservices in Spring
The Spring Framework offers extensive support for the development of microservices, capitalizing on its robust ecosystem. Developers can use Spring’s modules, such as Spring MVC for web services, Spring Data for data access, and Spring Security for authentication and authorization, to build modular and independent microservices.
However, While Spring Framework allows for a lot of customization, it might require more hands-on configuration, which could make things more complicated, especially in larger microservices setups.
3.2 Microservices in Spring Boot
Spring Boot is made to help create applications fast and make deploying microservices easier. It makes setting up and configuring microservices simpler by relying on conventions rather than requiring lots of manual steps. This makes it well-suited for smaller to medium-sized microservices, where a more standardized approach is beneficial.
Also, Spring Boot encourages packaging microservices as executable JAR files with embedded web servers. This self-contained deployment model simplifies deployment and facilitates the creation of standalone microservices that can run independently.
4. Testing
This section explores the differences between testing in Spring and Spring Boot and how each framework addresses the challenges of ensuring software quality.
4.1 Testing in the Spring
- Configuration:
- Spring Context Configuration: In Spring, we need to set up and configure the Spring context manually in our test classes. This may involve specifying XML configurations or using annotations like
@ContextConfiguration. Even though this method allows for flexibility, it might make the setup for tests long and need extra effort to keep everything maintained.
- Spring Context Configuration: In Spring, we need to set up and configure the Spring context manually in our test classes. This may involve specifying XML configurations or using annotations like
- Dependency Injection:
- Manual Injection: Dependency injection is a fundamental concept in Spring. We often need to manually inject dependencies into our test classes, either through annotations like
@Autowiredor constructor injection.
- Manual Injection: Dependency injection is a fundamental concept in Spring. We often need to manually inject dependencies into our test classes, either through annotations like
- Test Slicing:
- Limited Slicing: Spring allows for slicing tests, but it might involve more manual setup. We can use annotations like
@WebMvcTestor@DataJpaTestto focus on specific layers of our application.
- Limited Slicing: Spring allows for slicing tests, but it might involve more manual setup. We can use annotations like
4.2 Testing in Spring Boot
- Auto-Configuration:
- Automatic Context Configuration: Spring Boot simplifies testing through its auto-configuration feature. Tests in Spring Boot projects often benefit from automatically configured settings, reducing the need for extensive manual setup.
- Dependency Injection:
- Convenient Auto-Wiring: With Spring Boot, dependency injection is more straightforward. We can use annotations like
@SpringBootTestto automatically configure the application context for testing purposes.
- Convenient Auto-Wiring: With Spring Boot, dependency injection is more straightforward. We can use annotations like
- Embedded Servers:
- Embedded Server Integration: Spring Boot often involves testing with embedded servers like Tomcat or MockMvc, making it easier to perform integration tests for web applications without the need for external server setup.
- Test Slicing:
- Extensive Slicing: Spring Boot enhances test slicing, allowing for more specialized testing scenarios. Annotations like
@WebMvcTest,@DataJpaTest, and@SpringBootTestprovide more extensive slicing capabilities, making us focus on testing specific application layers, such as the web or data layer, without setting up the entire application context.
- Extensive Slicing: Spring Boot enhances test slicing, allowing for more specialized testing scenarios. Annotations like
5. Packaging and Deployment
Let’s explore the process of packaging and deploying an application using Spring Framework and Spring Boot.
5.1 Packaging and Deployment in Spring
Spring is modular and follows the principle of “DIY” (Do It Yourself), allowing developers to pick and choose the components they need for their applications.
5.1.1 Packaging in Spring
In a typical Spring application, packaging involves creating a WAR (Web Application Archive) file. A WAR file is a packaged web application that contains compiled Java classes, JAR files, configuration files, and web resources. It is then deployed to a servlet container, such as Apache Tomcat or Jetty.
5.1.2 Deployment in Spring
Deployment in Spring traditionally involves deploying the WAR file to a servlet container, which then takes care of handling the application’s runtime. Developers need to manage the container configuration and ensure that it is compatible with the Spring version and dependencies used in the application.
5.2 Packaging and Deployment in Spring Boot
Spring Boot, on the other hand, makes it easier to create applications ready for use in the real world. It prefers following established conventions instead of needing lots of configurations, and its goal is to make setting up and deploying Spring applications a less demanding task.
5.2.1 Packaging in Spring Boot
Spring Boot allows developers to create standalone JAR files that include an embedded web server, such as Tomcat, Jetty, or Undertow. This self-contained JAR contains all the necessary dependencies, making it easy to deploy and run the application with a simple java -jar command.
5.2.2 Deployment in Spring Boot
Deploying with Spring Boot is simple because it includes a built-in web server and a self-contained JAR. To deploy, you just run the JAR file, and Spring Boot handles everything, starting the embedded server and launching the application.
6. Project Structure – Spring vs Spring Boot
6.1 Traditional Spring Project Structure
In a regular Spring project, the organization is more hands-on and structured. Developers can arrange their code and resources the way they like, adapting to their preferences and project needs. The usual setup involves creating folders for controllers, services, repositories, configuration, and resources.
6.1.1 Configuration Files
In the usual Spring projects, we use XML or Java-based configuration files. These files, often named applicationContext.xml or annotated Java classes, describe the beans and how they’re connected in the application. Spring lets developers decide how to set up the project based on what they like and find convenient.
6.2 Spring Boot Project Structure
Spring Boot encourages the packaging of applications as executable JAR files. As a result, the project structure is optimized for this deployment model. The main application class often resides in the root package, and dependencies are bundled into a single JAR, reducing the complexity of deployment.
6.2.1 Application Properties
Spring Boot uses a single file called application.properties or application.yml to store all the configuration settings, like connecting to databases and setting server ports. This makes it easier to manage configurations compared to the scattered configuration files used in regular Spring projects.
7. Conclusion
In the course of this article, we have explored some distinctions between Spring vs Spring boot. In conclusion, choosing between Spring vs Spring Boot depends on the specific needs of our project. Spring is well-suited for large-scale enterprise applications with complex requirements. On the other hand, Spring Boot is an excellent choice for microservices, rapid prototyping, and projects where simplicity and convention-based configuration are prioritized.
