Spring Boot

@SpringBootApplication
public class RocketApplication {
    
    public static void main(String[] args) {
        SpringApplication.run(RocketApplication.class, args);
        System.out.println("🚀 Rocket launched successfully!");
    }
}

@RestController
public class LaunchController {
    
    @GetMapping("/launch")
    public String launch() {
        return "🚀 Mission started! Ready for takeoff!";
    }
}

@Entity
public class Astronaut {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    private String name;
    private String mission;
    private int experience;
    
    // Constructors, getters, and setters
}

@RestController
@RequestMapping("/api/astronauts")
public class AstronautController {
    
    @Autowired
    private AstronautRepository repository;
    
    @GetMapping
    public List<Astronaut> getAllAstronauts() {
        return repository.findAll();
    }
    
    @PostMapping
    public Astronaut createAstronaut(@RequestBody Astronaut astronaut) {
        return repository.save(astronaut);
    }
}

# application.properties
rocket.name=Apollo Mission
rocket.fuel-type=Liquid Oxygen
rocket.crew-size=3
rocket.mission-duration=7 days

server.port=8080
spring.datasource.url=jdbc:h2:mem:rocketdb
spring.jpa.show-sql=true

@ConfigurationProperties(prefix = "rocket")
@Component
public class RocketConfig {
    
    private String name;
    private String fuelType;
    private int crewSize;
    private String missionDuration;
    
    // Getters and setters
}