What is the difference between Spring and Spring Boot?

Question

I am new to Java development and I keep hearing about Spring and Spring Boot. What exactly is the difference between them?

I understand that Spring is a framework, but what does Spring Boot add on top of it? Should I learn Spring first before Spring Boot?

java_master · Accepted Answer

Spring is a comprehensive framework for building Java applications. It provides features like Dependency Injection, Aspect-Oriented Programming, Data Access, Transaction Management, etc.

Spring Boot is built ON TOP of Spring. It simplifies Spring development by providing:

1. **Auto-configuration** - Automatically configures Spring based on dependencies
2. **Starter POMs** - Pre-defined dependency descriptors (spring-boot-starter-web, etc.)
3. **Embedded Servers** - Tomcat/Jetty embedded, no need for WAR deployment
4. **Actuator** - Production-ready features like health checks, metrics

You don't need to learn all of Spring first. Start with Spring Boot directly - it will teach you Spring concepts as you go!

```java
// Spring Boot Application - minimal code!
@SpringBootApplication
public class MyApp {
    public static void main(String[] args) {
        SpringApplication.run(MyApp.class, args);
    }
}
```

1 Answer