1

I need to return a service info by id. I've tried different variations of writing my code but they all lead to java not seeing the value by its id.

Service Model:

@Entity
@Getter
@Setter
public class Service {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;
    private BigDecimal price;
}

Service:

public class ServiceService {
    @Autowired
    private ServiceRepo serviceRepo;

    public Service getById(Long id) {
        return serviceRepo.findById(id).get();
    }
}

Repository:

public interface ServiceRepo extends JpaRepository<Service, Long>, JpaSpecificationExecutor<Service> {
    Optional<Service> findById(Long id);
}

And conroller:

@Controller
public class AllServices {
    @Autowired
    private ServiceRepo serviceRepo;

    @GetMapping("/services")
    public String allServices(Model model){
        List<Service> services = serviceRepo.findAll();
        model.addAttribute("services", services);
        return "services";
    }

    @Autowired
    private ServiceService serviceService;

    @GetMapping("/services/{id}")
    public ResponseEntity<Service> getServiceById(@RequestParam(value = "id", required = false) Long id){
        try{
            Service service = serviceService.getById(id);
            return new ResponseEntity<>(service, HttpStatus.OK);
        }catch(NoSuchElementException e){
            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
        }
    }
}

When it comes to all services, it returns all values, but here it doesn't see them.

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These answers and many others didn't help:

JPA Repository.findById() returns null but the value is exist on db

Exception: org.springframework.web.bind.MissingServletRequestParameterException: Required String parameter 'params' is not present

nicole
  • 23
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  • You can try annotating your ```ServiceRepo``` with ```@Repository``` annotation and remove the ```findById(Long id)``` method declaration from this interface. Implementation for this method is already provided by ```SimpleJpaRepository```. So use the default one. – CyberMafia May 04 '23 at 16:22

2 Answers2

1

I see you're triying to use @RequestParam to get the param value, but you get the param like a @PathVariable, change the annotation to @PathVariable and try again.

I hope this link can help you.

https://www.baeldung.com/spring-pathvariable

Or if you want to use @RequestParam, so, send your request like: http://localhost:8080/service?id=1

AbrahamSantos
  • 169
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  • Oh, thank you! Using http://localhost:8080/service?id=1 returns 404 Not Found, using @PathVariable and http://localhost:8080/services/1 still Cannot invoke \"coursework.MassageSalon.services.ServiceService.getById(java.lang.Long)\" because \"this.serviceService\" is null :_( – nicole May 03 '23 at 15:20
1

Service class need to be annotated as such. Otherwise the @Autowired will not work.

Solution

Add the annotation like this:

@Service
public class ServiceService {
// ...
}
Mar-Z
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