Spring Boot webapp中的Orika ClassCastException

Question

在我正在研究的示例Spring Boot webapp中,将实体映射到DTO并使用Orika时,我遇到了一个奇怪的ClassCastException.当我尝试在嵌入式Tomcat中部署的应用程序上进行映射时,我得到了异常,但我可以在JUnit测试上下文中完成映射.这是相关的类(它们都非常简单):

JPA实体:

@Entity
public class Position {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;
    private String name;
    // getters/setters...
}

DTO:

public class PositionDto {

    private Integer id;
    private String name;
    // getters/setters...
}

休息控制器:

@RestController
public class PositionController {

    @Autowired
    private PositionService positionService;

    @RequestMapping("/position")
    public PositionDto get() {
        final PositionDto positionDto = positionService.getPosition(1);
        return positionDto;
    }
}

服务类:

@Service
public class PositionServiceImpl implements PositionService {

    @Autowired
    private PositionRepository positionRepository;
    @Autowired
    private OrikaBeanMapper mapper;

    @Transactional(readOnly = true)
    @Override
    public PositionDto getPosition(final Position.ID id) {
        // This returns a populated Position object with id=1 and name = "Creator"
        final Position position = positionRepository.findOne(id.getId());
        // This is where the mapping occurs
        return mapper.map(position, PositionDto.class);
    }
}

OrikaBeanMapper类:

@Component
public class OrikaBeanMapper extends ConfigurableMapper implements ApplicationContextAware {        

    public OrikaBeanMapper() {
        super(false);
    }

    @Override
    protected void configureFactoryBuilder(final   DefaultMapperFactory.Builder factoryBuilder) {
        factoryBuilder.mapNulls(false);
    }
    // Omitted non-important methods

}

这是ClassCastException的堆栈跟踪:

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is ma.glasnost.orika.MappingException: While attempting the following mapping:
sourceClass = class com.dlizarra.startuphub.position.Position
destinationType = com.dlizarra.startuphub.position.PositionDto
resolvedStrategy = InstantiateAndUseCustomMapperStrategy<Position, PositionDto> {customMapper: GeneratedMapper<Position, PositionDto> {usedConverters: [], usedMappers: [], usedMapperFacades: [], usedTypes: [] }, unenhancer: ma.glasnost.orika.unenhance.BaseUnenhancer@73c3e10e, objectFactory: DefaultConstructorObjectFactory<PositionDto>}
Error occurred: java.lang.ClassCastException: com.dlizarra.startuphub.position.Position cannot be cast to com.dlizarra.startuphub.position.Position
-----begin dump of current state-----------------------------
Registered object factories: 1 (approximate size: 110.8 kB)
    [PositionDto] : {Position=DefaultConstructorObjectFactory<PositionDto>}
-------------------------------------------------------------------------------
Registered mappers: 1 (approximate size: 17,643.0 kB)
    [0] : GeneratedMapper<Position, PositionDto> {usedConverters: [], usedMappers: [], usedMapperFacades: [], usedTypes: [] }
-------------------------------------------------------------------------------
Registered concrete types: 5 (approximate size: 294.3 kB)
  [interface java.util.List] : ArrayList<Object>
  [interface java.util.Set] : LinkedHashSet<Object>
  [interface java.util.Collection] : ArrayList<Object>
  [interface java.util.Map] : LinkedHashMap<Object, Object>
  [interface java.util.Map$Entry] : MapEntry<Object, Object>
  -------------------------------------------------------------------------------

Resolved strategies: 1 (approximate size: 19,850.8 kB)

{source: Position, dest: PositionDto, in-place:false}:  InstantiateAndUseCustomMapperStrategy<Position, PositionDto>
{customMapper: GeneratedMapper<Position, PositionDto> {usedConverters: [],    usedMappers: [], usedMapperFacades: [], usedTypes: [] }, unenhancer:
ma.glasnost.orika.unenhance.BaseUnenhancer@73c3e10e, objectFactory:
DefaultConstructorObjectFactory<PositionDto>}
-------------------------------------------------------------------------------
Unenhance strategy: ma.glasnost.orika.unenhance.BaseUnenhancer@73c3e10e
-----end dump of current state-------------------------------] with root cause
java.lang.ClassCastException: com.dlizarra.startuphub.position.Position cannot be cast to com.dlizarra.startuphub.position.Position
at ma.glasnost.orika.generated.Orika_PositionDto_Position_Mapper43322711137530$0.mapAtoB(Orika_PositionDto_Position_Mapper43322711137530$0.java) ~[orika-core-1.4.6.jar:na]
at ma.glasnost.orika.impl.mapping.strategy.UseCustomMapperStrategy.map(UseCustomMapperStrategy.java:67) ~[orika-core-1.4.6.jar:na]
at ma.glasnost.orika.impl.MapperFacadeImpl.map(MapperFacadeImpl.java:742) ~[orika-core-1.4.6.jar:na]

我真的不知道这里发生了什么.我没有得到它试图将位置投射到位置的地方.每个实体/ dto类都会发生这种情况,而不仅仅是位置.

当我单元测试任何方法时,我可以映射任何这些类没有问题,它完美地运行并且所有字段都被正确映射,所以我认为这不是Orika配置问题.仅当我在嵌入式Tomcat中部署webapp并且在其余控制器方法中调用映射方法时,才会发生异常.

这是一个简单的Spring Boot应用程序,这是我在其中编写的第一个休息端点.也许我在配置中遗漏了一些东西(我有@EnableAutoConfiguration所以没有那么多配置),但我无法猜测是什么让Orika抛出这个异常.

关于可能发生的事情的任何想法或提示将非常感激.

谢谢!

Answer 1

我刚刚意识到这个错误有一个解决方法,因为几个月前已经有了Spring Boot 1.4.0(我相信这是这个版本),当时他们介绍了通过属性文件自定义Dev Tools的可能性.

要解决这个问题,我们必须:

1. 在中创建一个META-INF文件夹src/main/resources.
2. spring-devtools.properties在其中创建文件.
3. 添加restart.include.orika=/orika-core.*\.jar到文件中.

正如所陈述的文档中,restart.include将拉动到"重启"的类加载器的任何广口瓶的匹配的正则表达式.所以我们将orika-core-1.4.6.jar文件包含在内.