PlayerService.kt

@Service
class PlayerService(val repository: PlayerRepository) {

    fun getAll(): List<Player> = repository.findAll()

    fun getById(id: Long): Player = repository.findByIdOrNull(id) ?: 
        throw ResponseStatusException(HttpStatus.NOT_FOUND)

    fun create(player: Player): Player = repository.save(player)

    fun remove(id: Long) {
        if (repository.existsById(id)) repository.deleteById(id)
        else throw ResponseStatusException(HttpStatus.NOT_FOUND)
    }

    fun update(id: Long, player: Player): Player {
        return if (repository.existsById(id)) {
            player.id = id
            repository.save(player)
        } else throw ResponseStatusException(HttpStatus.NOT_FOUND)
    }
}