Spring Boot Notes

Spring Boot makes it easy to create stand-alone, production-grade Spring-based applications.

Quick Start

# Create a new Spring Boot project
curl https://start.spring.io/starter.zip -d type=maven-project \
  -d language=java -d bootVersion=3.4.0 \
  -d groupId=com.example -d artifactId=demo \
  -o demo.zip

Project Structure

src/
├── main/
│   ├── java/com/example/demo/
│   │   ├── DemoApplication.java
│   │   ├── controller/
│   │   └── service/
│   └── resources/
│       └── application.yml
└── test/

Common Annotations

Annotation	Purpose
@SpringBootApplication	Entry point of a Spring Boot app
@RestController	RESTful controller
@RequestMapping	Map web requests
@Autowired	Dependency injection
@Service	Service layer component
@Repository	Data access layer component

REST Example

@RestController
@RequestMapping("/api/todos")
public class TodoController {

    @GetMapping
    public List<Todo> getAll() {
        return todoService.findAll();
    }

    @PostMapping
    public Todo create(@RequestBody Todo todo) {
        return todoService.save(todo);
    }
}