What it is
Spring Boot is a Spring project for quickly creating Java applications and services. It removes much of the manual configuration, derives settings from dependencies, and runs apps as normal Java processes.
It became a standard entry point into the Spring ecosystem for web services, REST APIs, internal apps, microservices, and batch jobs.
What is inside
The repository contains auto-configuration, starters, test support, Actuator, CLI/plugins, and integrations with many Spring projects. The README shows a minimal app with `@SpringBootApplication` and `SpringApplication.run`.
A practical flow is to create a project with Spring Initializr, choose dependencies, write a controller or service, run the app, and add database, security, metrics, health endpoints, and environment configuration.
Minimal application
This snippet shows the basic Spring Boot shape: one class starts the context and embedded server.
@SpringBootApplication
public class Example {
public static void main(String[] args) {
SpringApplication.run(Example.class, args);
}
}Strengths and limits
The strength is a mature ecosystem and fast startup for Java services. Starters and auto-configuration work well when an app follows common Spring patterns.
The limitation is hidden complexity. Auto-configuration saves time, but dependency conflicts or unusual architecture require understanding what Spring Boot enabled and how to override it.