Spring Boot 입문

// build.gradle
// implementation 'org.springframework.boot:spring-boot-starter-web'

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.*;

@SpringBootApplication
public class App {
    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }
}

@RestController
@RequestMapping("/api")
class UserController {

    @GetMapping("/hello")
    public String hello() {
        return "Hello, Spring Boot!";
    }

    @GetMapping("/users/{id}")
    public String getUser(@PathVariable Long id) {
        return "User ID: " + id;
    }
}

// GET /api/hello   → "Hello, Spring Boot!"
// GET /api/users/1 → "User ID: 1"