autowired依存関係の注入に失敗しました。フィールドをオートワイヤできませんでした

Question

この質問は多くの質問をしていますが、私は二重（または三重または四重）トピックを危険にさらしています。

私は多くの恐怖の問題を抱えています。初めから完全なSpringプロジェクトを最初に設定するので、問題の内容を実際には分かりません。

これが私の現在の設定です： ProjectRepo：

package be.italent.repo; 

import be.italent.model.Project; 
import org.springframework.data.jpa.repository.JpaRepository; 
import org.springframework.stereotype.Repository; 

@Repository 
public interface ProjectRepo extends JpaRepository<Project, Integer> { 

} 

ProjectService：

package be.italent.services; 

import be.italent.model.Project; 
import be.italent.repo.ProjectRepo; 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.stereotype.Service; 

import java.util.List; 

@Service 
public class ProjectService { 

    @Autowired 
    private ProjectRepo projectRepo; 

    public List<Project> getAllProjects() { 
     return projectRepo.findAll(); 
    } 
} 

ProjectRestController：

package be.italent.controllers; 

import java.util.ArrayList; 
import be.italent.services.ProjectService; 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.web.bind.annotation.RequestMapping; 
import org.springframework.web.bind.annotation.RequestMethod; 
import org.springframework.web.bind.annotation.RestController; 
import be.italent.model.Project; 

@RestController 
@RequestMapping("/projects") 
public class ProjectRestController { 

    @Autowired 
    private ProjectService projectService; 

    @RequestMapping(method = RequestMethod.GET, produces="application/json") 
    public ArrayList<Project> getProjects(){ 
     ArrayList<Project> c = (ArrayList<Project>) projectService.getAllProjects(); 

     return c; 
    } 
} 

春-mvc.xml

... 
<context:component-scan base-package="be.italent"></context:component-scan> 
... 

エラー：

SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'projectRestController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private be.italent.services.ProjectService be.italent.controllers.ProjectRestController.projectService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'projectService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [be.italent.repo.ProjectRepo] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:292) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1185) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:700) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5068) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5584) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:147) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1572) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1562) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private be.italent.services.ProjectService be.italent.controllers.ProjectRestController.projectService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'projectService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [be.italent.repo.ProjectRepo] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:508) at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:289) ... 22 more Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'projectService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [be.italent.repo.ProjectRepo] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:292) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1185) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195) at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1014) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:957) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:855) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:480) ... 24 more Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [be.italent.repo.ProjectRepo] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:508) at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:289) ... 35 more Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [be.italent.repo.ProjectRepo] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1100) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:960) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:855) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:480) ... 37 more

任意のヘルプ？ありがとう！

ソリューション

は私の春-mvc.xmlにこれを追加しました：

<beans 
... 
jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd"> 

... 

<jpa:repositories base-package="be.italent.repo" entity-manager-factory-ref="emf"/> 

Answer 1

をアプリケーション・コンテキストを初期化するときに何かが間違っている場合には、春には多くの場合、これらの長いスタックトレースを提供します。通常、スタックトレースの最下部を見ることで、最終的な原因を知ることができます。あなたのケースでは

あなたが一番下に、このエラーメッセージが表示されます。

org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [be.italent.repo.ProjectRepo] found

これは、春はタイプProjectRepoの豆を見つけることができないことを意味します。

あなたProjectRepoリポジトリインターフェイスは、コンポーネント・スキャンでbe.italentのサブパッケージであり、パッケージbe.italent.repo、であるので、問題は、それが間違ったパッケージ内にあることではありません。

Spring Data JPAを有効にすることを忘れましたか？

あなたは（あなたが今やっているように）、あなたは設定ファイルにrepositories XMLタグを持っている必要がXML構成を使用する場合：あなたはJavaConfigを使用する場合

<?xml version="1.0" encoding="UTF-8"?> 
<beans xmlns="http://www.springframework.org/schema/beans" 
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
     xmlns:jpa="http://www.springframework.org/schema/data/jpa" 
     xsi:schemaLocation="http://www.springframework.org/schema/beans 
      http://www.springframework.org/schema/beans/spring-beans.xsd 
      http://www.springframework.org/schema/data/jpa 
      http://www.springframework.org/schema/data/jpa/spring-jpa.xsd"> 

    <!-- Tell Spring Data JPA where your repository interfaces are --> 
    <jpa:repositories base-package="be.italent.repo" /> 

    <!-- ... --> 
</beans> 

は、アノテーションでそれを行うことができます。

@Configuration 
@EnableJpaRepositories("be.italent.repo") 
public class MySpringConfiguration { 
    // ... 
}