[FIXED] Spring Boot | Using a separate file for logic

Issue

I am writing a small CRUD in Spring and Java. And I want to use a separate file for writing logic, this is very convenient for me, I did this when developing with NestJS. I have a few questions, is it correct to do this in Spring, or should I do everything inside a function in the controller. And if I write logic in a separate file, I should mark the logic class as @Component and the functions inside it as @Bean, right? I am new to Spring and as I understand it, I have to do this in order for the application to work correctly and my functions to be in the application context.

AuthLogic.java

@Component
public class AuthLogic {
   @Bean
   public void register() {
       // code ... 
   }
}

AuthController.java

 @RestController
 public class AuthController {
    @RequestMapping(value = "/register", method = RequestMethod.POST)
    @ResponseStatus(HttpStatus.CREATED)
    public void register(@Valid @RequestBody UserDTO newUser) {
       // here I call the register function from AuthLogic
    }
 }

Solution

You can write your business logic in a new separate file at service layer. Suppose you name it as AuthService and you mark it with annotation @Service.

@Service
public class AuthService{
}

You can then Autowire it in your controller class.

@RestController
public class AuthController {

    @Autowired
    AuthService authService;
    
    @RequestMapping(value = "/register", method = RequestMethod.POST)
    @ResponseStatus(HttpStatus.CREATED)
    public void register(@Valid @RequestBody UserDTO newUser) {
       // here I call the register function from AuthLogic
    }
 }

Answered By - Drishti Jain
Answer Checked By - Cary Denson (JavaFixing Admin)