Spring - 来自另一个项目或 jar 的线组件

Question

如果这是一个基本问题，我很抱歉，但我对使用 Spring 还很陌生。

我在 Eclipse 中设置了 2 个 maven 项目，都使用 Spring。我希望一个项目在另一个项目中使用 Spring @Service。我试图通过使用 @Resource 注释来注释成员变量来做到这一点。我在 pom.xml 中添加了对另一个项目的依赖。

但是，当运行这个 Spring 时，没有找到我想在另一个项目中使用的类。为了让 Spring 在另一个项目中找到对象，我还需要做些什么吗？当所有代码都在一个项目中时它工作正常，所以我需要告诉它以某种方式扫描另一个项目吗？

我试过添加 @ComponentScan() 但这没有帮助。

编辑：回答人们对我的问题提出的问题。如果我对 Spring 做一些根本性的错误或者这是基本的东西，再次道歉。

因此，我有 2 个 Maven 项目，它们都是使用 Spring Tool Suite 作为 Spring Starter Projects 创建的。但是，Web 项目也不是，一个是命令行工具，另一个是该工具和其他项目使用的库。因此，两者都被创建为 JAR 文件。

该工具在 pom.xml 中依赖于作为库的项目。它构建得很好，我可以让 Maven 为它创建一个 JAR 文件等等。因为它们都是 Maven 项目，所以它们都具有标准的 Maven 文件结构，其中包含我在“src/main/java”中的一个包中的 Java 代码。

该工具运行使用：

SpringApplication.run(Application.class, args);

当我连接在一起的所有类都在同一个项目中时，这很好用。现在我已经将其中一些类移到另一个项目中，它不再找到它们。

接下来，我目前只使用Java注解来配置spring，而不是XML。所以我没有 XML：

<context:annotation:config/>

出现在任何地方。是否需要此 XML 来实现我想在这里做的事情？

最后，这是我得到的堆栈跟踪：

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'application': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.spormeon.adysis.openxdataretriever.services.OpenXDataHandler com.spormeon.adysis.openxdataretriever.Application.openxDataRetriever; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'openXDataHandler': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.spormeon.adysis.aws.dynamodb.loaders.InventoryReportLoader] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@javax.annotation.Resource(shareable=true, lookup=, name=, description=, authenticationType=CONTAINER, type=class java.lang.Object, mappedName=)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1202)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:686)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:957)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:946)
at com.spormeon.adysis.openxdataretriever.Application.main(Application.java:21)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.spormeon.adysis.openxdataretriever.services.OpenXDataHandler com.spormeon.adysis.openxdataretriever.Application.openxDataRetriever; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'openXDataHandler': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.spormeon.adysis.aws.dynamodb.loaders.InventoryReportLoader] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@javax.annotation.Resource(shareable=true, lookup=, name=, description=, authenticationType=CONTAINER, type=class java.lang.Object, mappedName=)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
... 15 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'openXDataHandler': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.spormeon.adysis.aws.dynamodb.loaders.InventoryReportLoader] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@javax.annotation.Resource(shareable=true, lookup=, name=, description=, authenticationType=CONTAINER, type=class java.lang.Object, mappedName=)}
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessPropertyValues(CommonAnnotationBeanPostProcessor.java:308)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1202)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
... 17 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.spormeon.adysis.aws.dynamodb.loaders.InventoryReportLoader] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@javax.annotation.Resource(shareable=true, lookup=, name=, description=, authenticationType=CONTAINER, type=class java.lang.Object, mappedName=)}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1301)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1047)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.autowireResource(CommonAnnotationBeanPostProcessor.java:457)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.getResource(CommonAnnotationBeanPostProcessor.java:435)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor$ResourceElement.getResourceToInject(CommonAnnotationBeanPostProcessor.java:559)
at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:169)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessPropertyValues(CommonAnnotationBeanPostProcessor.java:305)
... 28 more

Answer 1

感谢您的所有帮助，但我实际上发现了我做错了什么！

我使用了 @ComponentScan 注释，但没有在其他 Maven 项目中指定包。

添加它可以让一切按照我的要求工作。