// StudentController.java

@RestController

@RequestMapping("/students")

public class StudentController {

@Autowired

private StudentService studentService;

@GetMapping("/{id}")

public ResponseEntity getStudentById(@PathVariable Long id) {

return ResponseEntity.ok(studentService.getStudentById(id));

}

}

// StudentService.java

@Service

public class StudentService {

@Autowired

private StudentRepository studentRepository;

public Student getStudentById(Long id) {

return studentRepository.findById(id).orElse(null);

}

}