@Autowired 有效但 @Inject 无效

Question

我有一个注入以下内容的资源 class

@Component
public class CustomDozerBeanMapper implements Mapper {
    private final DozerBeanMapper beanMapper;

    public CustomDozerBeanMapper() {
        this.beanMapper = new DozerBeanMapper();
        BeanMappingBuilder builder = new BeanMappingBuilder() {
            protected void configure() {
                //some mapping stuff
            }
        };
        beanMapper.addMapping(builder);
    }

    @Override
    public <T> T map(Object o, Class<T> aClass) throws MappingException {
        return beanMapper.map(o, aClass);
    }

    @Override
    public void map(Object o, Object o1) throws MappingException {
        beanMapper.map(o, o1);
    }

    @Override
    public <T> T map(Object o, Class<T> aClass, String s) throws MappingException {
        return beanMapper.map(o, aClass, s);
    }

    @Override
    public void map(Object o, Object o1, String s) throws MappingException {
        beanMapper.map(o, o1, s);
    }
}

在我的 applicationContext.xml 我已经声明

<context:annotation-config/>
<context:component-scan base-package="foo.bar"/>
<bean id="customDozerMapper" class="foo.bar.CustomDozerBeanMapper" />

然后在我们的资源中我注入它

class SomeResource {
   @Inject CustomDozerMapper customDozerMapper;

   //We have loads of other Injects which work just fine, only this class has problems
}

Caused by: A MultiException has 1 exceptions.  They are:
1. org.glassfish.hk2.api.UnsatisfiedDependencyException: There was no object available for injection at SystemInjecteeImpl(requiredType=CustomDozerBeanMapper,parent=SomeResource,qualifiers={},position=-1,optional=false,self=false,unqualified=null,1098507248)

    at org.jvnet.hk2.internal.ThreeThirtyResolver.resolve(ThreeThirtyResolver.java:75)
    at org.jvnet.hk2.internal.Utilities.justInject(Utilities.java:947)
    at org.jvnet.hk2.internal.ServiceLocatorImpl.inject(ServiceLocatorImpl.java:975)
    at org.jvnet.hk2.internal.ServiceLocatorImpl.inject(ServiceLocatorImpl.java:965)
    at org.glassfish.jersey.server.spring.SpringComponentProvider$SpringManagedBeanFactory.provide(SpringComponentProvider.java:191)
    at org.jvnet.hk2.internal.FactoryCreator.create(FactoryCreator.java:153)
    at org.jvnet.hk2.internal.SystemDescriptor.create(SystemDescriptor.java:471)
    at org.jvnet.hk2.internal.PerLookupContext.findOrCreate(PerLookupContext.java:70)
    at org.jvnet.hk2.internal.Utilities.createService(Utilities.java:2072)
    at org.jvnet.hk2.internal.ServiceLocatorImpl.internalGetService(ServiceLocatorImpl.java:761)
    at org.jvnet.hk2.internal.ServiceLocatorImpl.getService(ServiceLocatorImpl.java:700)
    at org.glassfish.jersey.internal.inject.Injections.getOrCreate(Injections.java:172)
    at org.glassfish.jersey.server.model.MethodHandler$ClassBasedMethodHandler.getInstance(MethodHandler.java:284)
    at org.glassfish.jersey.server.internal.routing.PushMethodHandlerRouter.apply(PushMethodHandlerRouter.java:74)
    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:109)
    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:112)
    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:112)

现在，如果我更改并使用@Autowired，它就可以正常工作我们正在使用 Spring 进行依赖管理，但由于某种原因正在使用 h2k，我得到以下异常

任何人都可以解释可能是什么问题吗？

为什么它适用于@Autowired 而不是@Inject

为什么使用 h2k，而不是 Spring？

Answer 1

问题也可能是由于配置文件 customDozerMapper 中的 bean 名称和实际注入 customerDozerMapper 不匹配。如果 @inject 没有找到匹配的 bean，则抛出异常。但是，有 @autowired 的规定，您可以在其中设置属性 required=false，如果找不到匹配的 bean，它会注入 null。

Note: Configuration in config xml overrides the annotation configuration.

Answer 2

可能，问题可能是因为 2 个 bean 声明（一个在 XML 配置中，另一个在 @Component 配置中）并且 DI 容器无法获取其中一个他们。

此处可用的所有解决方案：

删除其中一个 bean 定义（我更喜欢 XML 一个）
通过 @Qualifier 或 @Named 注释指定一个 bean

@Autowired 有效但 @Inject 无效

@Autowired works but not @Inject

spring

dependency-injection

cdi