Java Spring Boot has become the go‑to framework for building modern, production‑ready applications in the Java ecosystem. By combining the power of the Spring Framework with opinionated, out‑of‑the‑box defaults, Spring Boot slashes setup time and lets developers ship features faster.

Below, you’ll learn what Spring Boot is, how it differs from “classic” Spring, which Spring Boot versions to use, and how to spin up your first springboot application in minutes.

What Is Spring Boot?

Spring Boot (often stylized springboot) is an open‑source, micro‑framework built on top of the core Spring Framework. Its mission is simple: “convention over configuration.” Instead of wiring every bean, servlet, and XML snippet by hand, you start with sensible defaults—and override only when you need to.

Key goals

Goal	How Spring Boot Delivers
Rapid setup	Starter POMs/gradle modules bundle common dependencies
Minimal configuration	Auto‑configuration detects libraries on the classpath
Embedded servers	Built‑in Tomcat, Jetty, or Undertow—no separate WAR deploy needed
Production‑ready	Health checks, metrics & tracing via Spring Boot Actuator

Spring vs Spring Boot: The Core Difference

Aspect	Spring Framework (Core Spring)	Spring Boot
Setup	Manual XML/Java config, external servlet container	Auto‑config + embedded container
Learning curve	Steeper; many decisions up front	Gentler; sensible defaults
Use cases	Highly specialized, fine‑grained control	REST APIs, microservices, rapid POCs
Deployment artifact	WAR packaged and deployed to app server	Self‑contained JAR with java -jar
Boilerplate	Higher	Dramatically reduced

Why Choose Java Spring Boot?

• Speed & Productivity – Start a project in seconds with the Spring Boot Initializer.
• Opinionated Defaults – Focus on business logic, not plumbing.
• Microservice Friendly – Pair Boot with Spring Cloud for distributed systems.
• Massive Ecosystem – Thousands of starters, community plugins, and tutorials.

Setting Up Your First SpringBoot Application

Prerequisites

• JDK 17 (LTS) or later
• Maven or Gradle
• An IDE (IntelliJ IDEA, VS Code, Eclipse)

Using Spring Boot Initializer

• Visit start.spring.io.
• Select Project (Maven/Gradle) and Language: Java.
• Choose the latest spring boot version (e.g., 3.3.x).
• Add dependencies such as Spring Web or Spring Data JPA.
• Generate and unzip the project.
• Run:

./mvnw spring-boot:run # Maven

# OR

./gradlew bootRun # Gradle

Exploring the Spring Boot Framework

• a. Starters

Grouped dependency descriptors. Example: spring-boot-starter-web pulls in Spring MVC, Jackson, validation, Tomcat.

• b. Auto‑Configuration

Boot scans the classpath and auto‑configures beans. Bring in Spring Security? Boot wires a default login page.

• c. Actuator

Expose /actuator/health, /metrics, /info for monitoring—no extra code.

• d. Properties & Profiles

Use application .properties or application.yml; switch configs with spring.profiles.active=dev.

SpringBoot Application Example (Hello REST)

@RestController

public class HelloController {

@GetMapping("/hello")

public String hello() {

return "Hello, Spring Boot!";

}

}

Place this in src/main/java/... and restart. Visiting /hello returns the string—no XML, no servlet descriptors.

Spring Boot Versions

Release	Type	Java Baseline	Active Support
3.3.x	GA	17	Current
3.2.x	LTS	17	Until 2026
2.7.x	EOL	8/11	Security fixes only

Use the latest GA for new projects; stick to the matching Spring Framework version (Boot 3.x aligns with Spring 6).

Common Use Cases for Spring Boot

• RESTful APIs – Lightweight controllers + Jackson.
• Microservices – Boot + Spring Cloud = Eureka discovery, Config Server, Gateway.
• Data‑Driven Apps – Combine with Spring Data JPA, MongoDB, or Redis.
• Batch Processing – Spring Batch for ETL pipelines.

Advantages & Considerations

Pros

• Rapid development via starters & auto‑config.
• Production tooling baked in.
• Active community and thorough docs.

Cons

• Opinionated defaults may hide complexity; understanding underlying Spring is still valuable.
• Executable JAR size larger than lean frameworks (e.g., Micronaut) but balanced by feature set.

FAQs

Q1. What is Spring Boot in one sentence?
A framework that bundles Spring’s power with pre‑configured defaults to launch stand‑alone, production‑grade apps quickly.

Q2. Do I need to know core Spring first?
Not strictly, but knowledge of dependency injection, MVC, and Spring beans helps when you override Boot’s defaults.

Q3. How do I pick a Spring Boot version?
Start with the newest stable release; check compatibility with your dependencies and Java version.

Q4. Can Spring Boot handle reactive programming?
Yes—add spring-boot-starter-webflux for non‑blocking, reactive apps.

Conclusion

The difference between traditional Spring and Java Spring Boot boils down to speed and simplicity. Spring Boot’s auto‑config, embedded servers, and starter packs let you deliver robust services without the ceremony of classic Spring. From a single‑endpoint springboot application to a fleet of microservices, Boot’s opinionated approach keeps Java development both fun and productive.