考虑在配置中定义'org.modelmapper.ModelMapper‘类型的bean

Question

应用程序启动失败

Kodlama.io.Devs.business.concretes.ProgrammingLanguageManager中构造函数的参数1需要一个无法找到的'org.modelmapper.ModelMapper‘类型的bean。

考虑在您的配置中定义'org.modelmapper.ModelMapper‘类型的bean。

ProgrammingLanguageManager

@Service
public class ProgrammingLanguageManager implements ProgrammingLanguageService {

    @Autowired
    private ProgrammingLanguageRepository programmingLanguageRepository;
    private ModelMapper modelMapper;

    @Autowired
    public ProgrammingLanguageManager(ProgrammingLanguageRepository programmingLanguageRepository,
            ModelMapper modelMapper) {
        this.programmingLanguageRepository = programmingLanguageRepository;
        this.modelMapper = modelMapper;

    }

    // * * * CRUD OPERATIONS * * *

    @Override
    public CreateProgrammingLanguageResponse add(CreateProgrammingLanguageRequest createProgrammingLanguageRequest)
            throws Exception {
        nameCannotBeSame(createProgrammingLanguageRequest.getName());

        ProgrammingLanguage programmingLanguage = modelMapper.map(createProgrammingLanguageRequest,
                ProgrammingLanguage.class);
        ProgrammingLanguage saveProgrammingLanguageResult = programmingLanguageRepository.save(programmingLanguage);

        CreateProgrammingLanguageResponse createProgrammingLanguageResponse = modelMapper
                .map(saveProgrammingLanguageResult, CreateProgrammingLanguageResponse.class);

        return createProgrammingLanguageResponse;
    }

    @Override
    public UpdateProgrammingLanguageResponse update(UpdateProgrammingLanguageRequest updateProgrammingLanguageRequest)
            throws Exception {
        nameCannotBeSame(updateProgrammingLanguageRequest.getName());

        ProgrammingLanguage programmingLanguage = modelMapper.map(updateProgrammingLanguageRequest,
                ProgrammingLanguage.class);
        ProgrammingLanguage saveProgrammingLanguageResult = programmingLanguageRepository.save(programmingLanguage);

        UpdateProgrammingLanguageResponse updateProgrammingLanguageResponse = modelMapper
                .map(saveProgrammingLanguageResult, UpdateProgrammingLanguageResponse.class);

        return updateProgrammingLanguageResponse;
    }

    @Override
    public DeleteProgrammingLanguageResponse delete(DeleteProgrammingLanguageRequest deleteProgrammingLanguageRequest) {

        ProgrammingLanguage getReferenceByIdProgrammingLanguageResult = programmingLanguageRepository
                .getReferenceById(deleteProgrammingLanguageRequest.getId());
        programmingLanguageRepository.delete(getReferenceByIdProgrammingLanguageResult);

        DeleteProgrammingLanguageResponse deleteProgrammingLanguageResponse = modelMapper
                .map(getReferenceByIdProgrammingLanguageResult, DeleteProgrammingLanguageResponse.class);

        return deleteProgrammingLanguageResponse;
    }

    // * * * GET METHODS * * *

    @Override
    public List<GetAllProgrammingLanguagesResponse> getAll() {

        List<ProgrammingLanguage> findAllProgrammingLanguageResult = programmingLanguageRepository.findAll();

        return modelMapper.map(findAllProgrammingLanguageResult,
                new TypeToken<List<GetAllProgrammingLanguagesResponse>>() {
                }.getType());
    }

    @Override
    public GetByIdProgrammingLanguageResponse getById(
            GetByIdProgrammingLanguageRequest getByIdProgrammingLanguageRequest) {

        ProgrammingLanguage getReferenceByIdProgrammingLanguageResult = programmingLanguageRepository
                .getReferenceById(getByIdProgrammingLanguageRequest.getId());

        GetByIdProgrammingLanguageResponse getByIdProgrammingLanguageResponse = modelMapper
                .map(getReferenceByIdProgrammingLanguageResult, GetByIdProgrammingLanguageResponse.class);

        return getByIdProgrammingLanguageResponse;
    }

    public GetByNameProgrammingLanguageResponse getByName(
            GetByNameProgrammingLanguageRequest getByNameProgrammingLanguageRequest) {

        ProgrammingLanguage getReferenceByNameProgrammingLanguageResult = new ProgrammingLanguage();
        getReferenceByNameProgrammingLanguageResult = programmingLanguageRepository
                .getByName(getByNameProgrammingLanguageRequest.toString());

        GetByNameProgrammingLanguageResponse getByNameProgrammingLanguageResponse = modelMapper
                .map(getReferenceByNameProgrammingLanguageResult, GetByNameProgrammingLanguageResponse.class);

        return getByNameProgrammingLanguageResponse;
    }

    // * * * BUSINESS RULES * * *

    private void nameCannotBeSame(String name) throws Exception {

        ProgrammingLanguage programmingLanguage = programmingLanguageRepository.getByName(name);

        var result = programmingLanguage;

        if (result != null) {
            throw new Exception(Messages.NAME_ALREADY_EXISTS);
        }
    }
}

我错过了什么，但我不知道

Answer 1

您的ModelMapper类没有注册为spring，它只是一个普通的java类。为了解决这个问题，您需要创建一个@Configuration类，如果您想自动使用它，它将定义bean。

@Configuration
public class AppConfiguration {
    @Bean
    public ModelMapper modelMapper() {
        return new ModelMapper();
    }
} 

否则，您无法启动依赖项注入，您必须使用new ModelMapper();自己创建该对象。

另一个技巧是避免使用@Autowire对字段进行注释。构造函数级注释就足够了。

Answer 2

从错误消息中可以清楚地看到，bean of type 'org.modelmapper.ModelMapper'丢失了。因此，请将以下bean添加到项目中，然后再试一次。

@Bean
public ModelMapper modelMapper() {
    return new ModelMapper();
}

注意:在带有@Configuration__注释的类中添加了这个bean。