登录
当前位置： 首页 > 知识库问答 >
问题：

防止mapstruct使用对象映射函数列表中的单个对象映射函数

欧阳元魁
2023-03-14

我有2个微服务：我们称它们为A和B。

由B处理的实体（其中引用了a的实体）被实现为简单的长id（例如groupId）

@Getter
@Setter
@NoArgsConstructor
@Entity
@Table(name = "WorkShifts")
@AllArgsConstructor
@Builder(toBuilder = true)
public class WorkShiftEntity extends BaseEntitySerial {
    @Column(name = "group_id")
    private Long groupId;
    private String description;
    @Column(name = "start_time")
    private Time startTime;
    @Column(name = "end_time")
    private Time endTime;
    @Column(name = "work_shift")
    private Integer workShift;
}

我想要实现的是使用mapstruct填充B(由A持有)的缺失组数据。到目前为止，我尝试使用@AfterMapping函数向a请求缺失的数据。我的映射器是:

@Mapper(componentModel = "spring", uses = LocalTimeMapper.class, builder = @Builder(disableBuilder = true), config = CommonMapperConfig.class)
public abstract class WorkShiftMapper extends BaseMapper implements IBaseMapper<WorkShiftEntity, WorkShiftDTO, Long>, LogSupport {
    @Autowired
    RestTemplate restTemplate;

    @Mapping(target = "groupId", source = "group.id")
    public abstract WorkShiftEntity dtoToEntity(WorkShiftDTO workShiftDTO);

    @AfterMapping
    public void afterEntityToDto(final WorkShiftEntity workShiftEntity, @MappingTarget final WorkShiftDTO workShiftDTO) {
        if (workShiftEntity == null) {
            return;
        }
        GroupDTO groupDTO = EcofinderUtils.getGroupDTO(restTemplate, workShiftEntity.getGroupId());

        try {
            GenericUtils.enhanceDTOForAttributeWithDTO(workShiftDTO, groupDTO, "group");
        } catch (InvocationTargetException | NoSuchMethodException | IllegalAccessException e) {
            getLogger().error(e.getMessage());
        }
    }

    @AfterMapping
    public void afterEntityToDtoList(final List<WorkShiftEntity> workShiftEntity, @MappingTarget final List<WorkShiftDTO> workShiftDTO) {
        if (workShiftEntity == null || workShiftEntity.size() == 0) {
            return;
        }

        List<GroupDTO> groups = EcofinderUtils.getAllGroupDTOById(restTemplate, workShiftEntity.stream().map(WorkShiftEntity::getGroupId).distinct().toList());

        try {
            //Compile the resulting DTOs with the data got from the registry
            //Group
            GenericUtils.enhanceDTOListWithDataFromDTOJoiningEntities(workShiftDTO, groups, workShiftEntity, "group", "groupId");
        } catch (AppException | InvocationTargetException | NoSuchMethodException | IllegalAccessException e) {
            getLogger().error(e.getMessage());
        }
    }
}

给我映射功能的实现接口是：

public interface IBaseMapper<T extends BaseEntity<K>, D extends IBaseDTO<K>, K extends Serializable> {
    D entityToDto(T entity);

    List<D> entityToDtoList(List<T> entity);

    T dtoToEntity(D dto);
}

生成的代码的问题在于，将实体列表映射到DTO列表的函数对每个实体使用EntityToToTo，导致n个请求到a。之后，调用另一个@AfterMapping函数（仅在一个请求中收集所有ID并提取所有数据的函数，这是映射列表时唯一应该使用的函数）。

    //GENERATED CODE BY MAPSTRUCT
    @Override
    public WorkShiftDTO entityToDto(WorkShiftEntity workShiftEntity) {
        if ( workShiftEntity == null ) {
            return null;
        }

        WorkShiftDTO workShiftDTO = new WorkShiftDTO();

        workShiftDTO.setId( workShiftEntity.getId() );
        workShiftDTO.setDescription( workShiftEntity.getDescription() );
        workShiftDTO.setStartTime( localTimeMapper.map( workShiftEntity.getStartTime() ) );
        workShiftDTO.setEndTime( localTimeMapper.map( workShiftEntity.getEndTime() ) );
        workShiftDTO.setWorkShift( workShiftEntity.getWorkShift() );

        afterEntityToDto( workShiftEntity, workShiftDTO );

        return workShiftDTO;
    }
    @Override
    public List<WorkShiftDTO> entityToDtoList(List<WorkShiftEntity> entity) {
        //more code...
        List<WorkShiftDTO> list = new ArrayList<WorkShiftDTO>( entity.size() );
        for ( WorkShiftEntity workShiftEntity : entity ) {
            list.add( entityToDto( workShiftEntity ) );
        }

        afterEntityToDtoList( entity, list );

        return list;
    }

有没有办法让mapstruct实现entityToDto函数两次，其中一个版本使用@AfterMapping函数，另一个版本不使用，以便让EntityToTodToList函数使用不带@AfterMapping调用的版本？

类似于:

    @Override
    public WorkShiftDTO entityToDto(WorkShiftEntity workShiftEntity) {
        if ( workShiftEntity == null ) {
            return null;
        }

        WorkShiftDTO workShiftDTO = new WorkShiftDTO();

        workShiftDTO.setId( workShiftEntity.getId() );
        workShiftDTO.setDescription( workShiftEntity.getDescription() );
        workShiftDTO.setStartTime( localTimeMapper.map( workShiftEntity.getStartTime() ) );
        workShiftDTO.setEndTime( localTimeMapper.map( workShiftEntity.getEndTime() ) );
        workShiftDTO.setWorkShift( workShiftEntity.getWorkShift() );

        afterEntityToDto( workShiftEntity, workShiftDTO );

        return workShiftDTO;
    }
    public WorkShiftDTO entityToDtoNoAfter(WorkShiftEntity workShiftEntity) {
        if ( workShiftEntity == null ) {
            return null;
        }

        WorkShiftDTO workShiftDTO = new WorkShiftDTO();

        workShiftDTO.setId( workShiftEntity.getId() );
        workShiftDTO.setDescription( workShiftEntity.getDescription() );
        workShiftDTO.setStartTime( localTimeMapper.map( workShiftEntity.getStartTime() ) );
        workShiftDTO.setEndTime( localTimeMapper.map( workShiftEntity.getEndTime() ) );
        workShiftDTO.setWorkShift( workShiftEntity.getWorkShift() );

        return workShiftDTO;
    }
    @Override
    public List<WorkShiftDTO> entityToDtoList(List<WorkShiftEntity> entity) {
        //more code...
        List<WorkShiftDTO> list = new ArrayList<WorkShiftDTO>( entity.size() );
        for ( WorkShiftEntity workShiftEntity : entity ) {
            list.add( entityToDtoNoAfter( workShiftEntity ) );
        }

        afterEntityToDtoList( entity, list );

        return list;
    }

其他方法也很受欢迎，这种方法对我来说只是感觉更自然。

提前致谢！

共有1个答案

公西修文
2023-03-14

经过大约两天的深入研究和多次尝试，我想我已经找到了一个不错的解决方案。

我可以给这些函数一个名字，这样它们就像有一个特定的作用域一样工作。映射器界面变成:

public interface IBaseMapper<T extends BaseEntity<K>, D extends IBaseDTO<K>, K extends Serializable> {
    @BeanMapping(qualifiedByName = "EntityToDTO")
    D entityToDto(T entity);

    @Named("EntityToDTOList")
    public abstract D entityToDTOListEntity(T entity);

    @IterableMapping(qualifiedByName = "EntityToDTOList")
    List<D> entityToDtoList(List<T> entity);

    T dtoToEntity(D dto);
}

这样我就可以把我需要的所有功能组合在一起。

映射器抽象类：

    @Mapping(target = "groupId", source = "group.id")
    public abstract WorkShiftEntity dtoToEntity(WorkShiftDTO workShiftDTO);

    @AfterMapping
    @Named("EntityToDTO")
    public void afterEntityToDto(final WorkShiftEntity workShiftEntity, @MappingTarget final WorkShiftDTO workShiftDTO) {
        if (workShiftEntity == null) {
            return;
        }
        GroupDTO groupDTO = EcofinderUtils.getGroupDTO(restTemplate, workShiftEntity.getGroupId());

        try {
            GenericUtils.enhanceDTOForAttributeWithDTO(workShiftDTO, groupDTO, "group");
        } catch (InvocationTargetException | NoSuchMethodException | IllegalAccessException e) {
            getLogger().error(e.getMessage());
        }
    }

    @AfterMapping
    @Named("EntityToDTOList")
    public void afterEntityToDtoList(final List<WorkShiftEntity> workShiftEntity, @MappingTarget final List<WorkShiftDTO> workShiftDTO) {
        if (workShiftEntity == null || workShiftEntity.size() == 0) {
            return;
        }

        List<GroupDTO> groups = EcofinderUtils.getAllGroupDTOById(restTemplate, workShiftEntity.stream().map(WorkShiftEntity::getGroupId).distinct().toList());

        try {
            //Compile the resulting DTOs with the data got from the registry
            //Group
            GenericUtils.enhanceDTOListWithDataFromDTOJoiningEntities(workShiftDTO, groups, workShiftEntity, "group", "groupId");
        } catch (AppException | InvocationTargetException | NoSuchMethodException | IllegalAccessException e) {
            getLogger().error(e.getMessage());
        }
    }

通过这样做，生成的Impl类是：

@Generated(
    value = "org.mapstruct.ap.MappingProcessor",
    date = "2022-05-20T15:08:38+0200",
    comments = "version: 1.4.2.Final, compiler: javac, environment: Java 17.0.1 (Oracle Corporation)"
)
@Component
public class WorkShiftMapperImpl extends WorkShiftMapper {

    @Autowired
    private LocalTimeMapper localTimeMapper;

    @Override
    public WorkShiftDTO entityToDto(WorkShiftEntity entity) {
        if ( entity == null ) {
            return null;
        }

        WorkShiftDTO workShiftDTO = new WorkShiftDTO();

        workShiftDTO.setId( entity.getId() );
        workShiftDTO.setDescription( entity.getDescription() );
        workShiftDTO.setStartTime( localTimeMapper.map( entity.getStartTime() ) );
        workShiftDTO.setEndTime( localTimeMapper.map( entity.getEndTime() ) );
        workShiftDTO.setWorkShift( entity.getWorkShift() );

        afterEntityToDto( entity, workShiftDTO );

        return workShiftDTO;
    }

    @Override
    public WorkShiftDTO entityToDTOListEntity(WorkShiftEntity entity) {
        if ( entity == null ) {
            return null;
        }

        WorkShiftDTO workShiftDTO = new WorkShiftDTO();

        workShiftDTO.setId( entity.getId() );
        workShiftDTO.setDescription( entity.getDescription() );
        workShiftDTO.setStartTime( localTimeMapper.map( entity.getStartTime() ) );
        workShiftDTO.setEndTime( localTimeMapper.map( entity.getEndTime() ) );
        workShiftDTO.setWorkShift( entity.getWorkShift() );

        return workShiftDTO;
    }

    @Override
    public List<WorkShiftDTO> entityToDtoList(List<WorkShiftEntity> entity) {
        if ( entity == null ) {
            return null;
        }

        List<WorkShiftDTO> list = new ArrayList<WorkShiftDTO>( entity.size() );
        for ( WorkShiftEntity workShiftEntity : entity ) {
            list.add( entityToDTOListEntity( workShiftEntity ) );
        }

        afterEntityToDtoList( entity, list );

        return list;
    }

    @Override
    public WorkShiftEntity dtoToEntity(WorkShiftDTO workShiftDTO) {
        if ( workShiftDTO == null ) {
            return null;
        }

        WorkShiftEntity workShiftEntity = new WorkShiftEntity();

        workShiftEntity.setGroupId( workShiftDTOGroupId( workShiftDTO ) );
        workShiftEntity.setId( workShiftDTO.getId() );
        workShiftEntity.setDescription( workShiftDTO.getDescription() );
        workShiftEntity.setStartTime( localTimeMapper.map( workShiftDTO.getStartTime() ) );
        workShiftEntity.setEndTime( localTimeMapper.map( workShiftDTO.getEndTime() ) );
        workShiftEntity.setWorkShift( workShiftDTO.getWorkShift() );

        return workShiftEntity;
    }

    private Long workShiftDTOGroupId(WorkShiftDTO workShiftDTO) {
        if ( workShiftDTO == null ) {
            return null;
        }
        GroupDTO group = workShiftDTO.getGroup();
        if ( group == null ) {
            return null;
        }
        Long id = group.getId();
        if ( id == null ) {
            return null;
        }
        return id;
    }
}

这正是我想要的。

 类似资料：

相关问答

用mapstruct映射嵌套对象MapStruct映射器返回空的映射对象使用Mapstruct和MyBatis映射嵌套列表对象要映射的对象的映射列表[重复]MapStruct：如何映射as源只有一个对象的对象列表

相关文章

Hibernate映射中的值对象还是实体对象？反应：映射对象的嵌套数组将JDBC ResultSet映射到对象将JSON映射到类对象类对象与哈希映射

相关阅读

JPA一对一映射Elasticsearch映射Dart映射ECharts 数据的视觉映射内存映射

相关工具

SPT 对象数据库iOS的函数响应型编程《函数式编程指南》五子棋单机对战版基于cocos2d-x的对对碰

相关文档

蜻蜓映射帮助文档Python 面向对象Microsoft Office 对象参考Linux C 函数 使用手册XmlHttp 对象参考手册
快捷导航： 新手教程 算法原理 架构设计 Java进阶 数据库进阶 大厂专栏 面试经验 编程笔记 编程问答 所有专题 文档资料 工具软件 电子书籍 小牛导航
在线工具： 房贷计算器 个税计算器 Linux命令查询 Json格式化 正则表达式 颜色转换 AES加解密 SHA1加密 MD5加密 毒鸡汤 字数统计 随机密码生成 进制转换 Base64编解码 励志句子
Copyright © 2019-2024 小牛知识库@xnip.cn. All Rights Reserved.