java - Spring Data Repository Autowiring 失败-6ren

java - Spring Data Repository Autowiring 失败

转载作者：IT老高更新时间：2023-10-28 13:44:22

我在这个问题上工作了很长一段时间，但无法让它工作。希望你们中的一些人能抽出时间来帮助我。

场景
我正在构建一个使用 Spring MVC 的 Web 应用程序。这个 webapp 应该使用另一个包含持久层的 Maven 项目。持久层目前只包含一个服务和一个 Spring Data 存储库。持久层本身对本地 MySQL 实例起作用。

我的问题
我对持久层进行了 JUnit 测试。测试加载并保存实体。这是通过服务处理的。两种操作都可以正常工作。

现在我正在 webapp 的 Maven 项目中的 JUnit 测试中尝试相同的方法。我再次尝试保存和加载实体。但这一次失败了。 Spring 声明服务内部的 Repository 引用无法 Autowiring ，因为没有适合的 bean。

我尝试了多种方法来解决这个问题。例如使用直接接线，给出限定符等等。我的方法都没有奏效。我什至构建了两个完整的新 Maven 项目，在其中简化了场景，但保留了必要的元素。在那里它就像一个魅力。我不明白我在这方面做错了什么，因为我从工作示例中调整了设置。

持久性项目中的文件

persistence.xml

 <?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"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"

       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
          http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
          http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
          http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd" default-autowire="byName">

    <tx:annotation-driven transaction-manager="transactionManager" />
    <context:annotation-config />

    <context:component-scan base-package="com.company.dev.webapp" />
    <jpa:repositories base-package="com.company.dev.webapp.repository" query-lookup-strategy="create-if-not-found" />

    <bean id="exceptionPostProcessor" class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />

    <!-- Data Source -->
    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close" >
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url" value="jdbc:mysql://localhost/webapp" />
        <property name="username" value="root" />
        <property name="password" value="" />
        <property name="initialSize" value="20" />
    </bean>

    <!-- Hibernate -->
    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="persistenceUnitName" value="webapp-persistence" />
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <property name="showSql" value="true" />
                <property name="generateDdl" value="true" />
                <property name="database" value="MYSQL" />
            </bean>
        </property>
    </bean>

    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory" />
    </bean>
</beans>

问题服务

@NoRepositoryBean
public interface QuestionService extends QuestionRepository {
   Question findById(Long id);

   Question findByUniqueRef(String uniqueRef);

   List<Question> findAll(Sort sort, Page page);

   List<Question> findAll(Page page);
}

QuestionServiceImpl

@Transactional
@Service
public class QuestionServiceImpl implements QuestionService {

    @Autowired
    QuestionRepository questionRepository;

    @Override
    public Question save(Question entity) {
        return questionRepository.save(entity);
    }
    [Some methods ommited]
}

问题库

@Transactional
@Repository
public interface QuestionRepository extends JpaRepository<Question, Long>{

}

来自 webapp 项目的文件

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">

  <!-- Spring Bind Macro -->
    <context-param> 
        <param-name>defaultHtmlEscape</param-name> 
        <param-value>true</param-value> 
    </context-param> 

  <!-- Log4J -->
    <context-param> 
        <param-name>log4jConfigLocation</param-name> 
        <param-value>/WEB-INF/log4j.xml</param-value> 
    </context-param> 
    <context-param> 
        <param-name>log4jRefreshInterval</param-name> 
        <param-value>15000</param-value> <!-- intervall in millisekunden!!! --> 
    </context-param> 
    <context-param> 
        <description>Zur Konfiguration von Log4j</description> 
        <param-name>webAppRootKey</param-name> 
    <!-- Diesen Wert bei jeder Anwendung anpassen! -->
        <param-value>app.root</param-value> 
    </context-param> 

    <!-- Application Context -->    
    <listener>
        <listener-class>
            org.springframework.web.context.ContextLoaderListener
        </listener-class>
    </listener>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            classpath:persistence-context.xml
            /WEB-INF/spring/app-config.xml
        </param-value>
    </context-param>


  <!-- Reads request input using UTF-8 encoding -->
    <filter>
        <filter-name>characterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>characterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

  <!-- Enables clean URLs with JSP views e.g. /welcome instead of /app/welcome -->
    <filter>
        <filter-name>UrlRewriteFilter</filter-name>
        <filter-class>org.tuckey.web.filters.urlrewrite.UrlRewriteFilter</filter-class>
    </filter>

    <filter-mapping>
        <filter-name>UrlRewriteFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

  <!-- Log4j Konfiguration laden-->
    <listener> 
        <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class> 
    </listener>

  <!-- Handles all requests into the application -->
    <servlet>
        <servlet-name>Spring MVC Dispatcher Servlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>
                /WEB-INF/spring/mvc-config.xml
            </param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>Spring MVC Dispatcher Servlet</servlet-name>
        <url-pattern>/app/*</url-pattern>
    </servlet-mapping>

    <filter>
        <filter-name>oemInViewFilter</filter-name>
        <filter-class>
            org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter
        </filter-class>
        <init-param>
            <param-name>entityManagerFactoryBeanName</param-name>
            <param-value>entityManagerFactory</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>oemInViewFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

</web-app>

app-config.xml

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        ">

  <!-- Application Message Bundle -->
    <bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
        <property name="basename" value="/WEB-INF/messages/messages"/>
        <property name="cacheSeconds" value="0"/>
    </bean>

  <!-- Services and Repositories -->
    <bean class="com.company.dev.webapp.impl.SimpleQuestionRepository" id="questionRepository">
    <!-- ... -->
    </bean>

  <!-- Events -->
    <bean class="com.company.dev.webapp.event.impl.ApplicationContextEventGateway" id="eventGateway"/>

  <!-- Search and indexing -->
    <import resource="search-indexing.xml"/>

</beans>

mvc-config.xml

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        ">

  <!-- Application Message Bundle -->
    <bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
        <property name="basename" value="/WEB-INF/messages/messages"/>
        <property name="cacheSeconds" value="0"/>
    </bean>

  <!-- Services and Repositories -->
    <bean class="com.company.dev.webapp.impl.SimpleQuestionRepository" id="questionRepository">
    <!-- ... -->
    </bean>

  <!-- Events -->
    <bean class="com.company.dev.webapp.event.impl.ApplicationContextEventGateway" id="eventGateway"/>    
</beans>

JUnit 测试

@RunWith(SpringJUnit4ClassRunner.class)
@TransactionConfiguration
@ContextConfiguration({"classpath:persistence-context.xml", "classpath:app-config.xml"})
@Transactional
public class QuestionServiceTest {

    @Autowired
    private QuestionService questServ;
    private Question quest;

    @Before
    public void setUp() throws Exception {
        if (quest == null) {
            quest = new Question();
            quest.setQuestion("Why?!");
            quest.setText("Please help!");
            quest.setCreationDate(new Date(System.currentTimeMillis()));
            questServ.save(quest);
        }
    }

    @Test
    public void loadQuestion() {
        Question check = questServ.findOne(quest.getId());
        Assert.assertNotNull(check);
        Assert.assertEquals(check, quest);
    }
}

异常(exception)

08:28:59 ERROR [test.context.TestContextManager]: Caught exception while allowing TestExecutionListener [org.springframework.test.context.support.DependencyInjectionTestExecutionListener@15a3a1] to prepare test instance [com.company.dev.webapp.service.QuestionServiceTest@a9a32c]
java.lang.IllegalStateException: Failed to load ApplicationContext
    at org.springframework.test.context.TestContext.getApplicationContext(TestContext.java:308)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:109)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:75)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:333)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:220)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:301)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:303)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:240)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:180)
    at junit.framework.JUnit4TestAdapter.run(JUnit4TestAdapter.java:39)
    at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.run(JUnitTestRunner.java:518)
    at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.launch(JUnitTestRunner.java:1052)
    at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.main(JUnitTestRunner.java:906)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'answerController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.company.dev.webapp.service.QuestionService com.company.dev.webapp.web.AnswerController.questionRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'questionServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.company.dev.webapp.repository.QuestionRepository com.company.dev.webapp.service.impl.QuestionServiceImpl.questionRepository; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.company.dev.webapp.repository.QuestionRepository] 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:286)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1064)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:574)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:84)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:1)
    at org.springframework.test.context.TestContext.loadApplicationContext(TestContext.java:280)
    at org.springframework.test.context.TestContext.getApplicationContext(TestContext.java:304)
    ... 24 more
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.company.dev.webapp.service.QuestionService com.company.dev.webapp.web.AnswerController.questionRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'questionServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.company.dev.webapp.repository.QuestionRepository com.company.dev.webapp.service.impl.QuestionServiceImpl.questionRepository; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.company.dev.webapp.repository.QuestionRepository] 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:507)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:283)
    ... 38 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'questionServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.company.dev.webapp.repository.QuestionRepository com.company.dev.webapp.service.impl.QuestionServiceImpl.questionRepository; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.company.dev.webapp.repository.QuestionRepository] 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:286)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1064)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:838)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:780)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:697)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:478)
    ... 40 more
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.company.dev.webapp.repository.QuestionRepository com.company.dev.webapp.service.impl.QuestionServiceImpl.questionRepository; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.company.dev.webapp.repository.QuestionRepository] 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$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:507)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:283)
    ... 51 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.company.dev.webapp.repository.QuestionRepository] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:914)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:783)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:697)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:478)
    ... 53 more

这是整个代码。如果还需要什么，请现在告诉我。感谢您对这个主题的帮助，因为我真的不知道如何解决这个问题。

最好的问候

最佳答案

我找到了解决方案。在编写了 QuestionRepository 的自定义实现并直接通过 xml 连接它之后，出现了一个新的异常，它解决了这个谜团。 bean 声明

<!-- Services and Repositories -->
    <bean class="com.company.dev.company.impl.SimpleQuestionRepository" id="questionRepository">
    <!-- ... -->
    </bean>

旨在提供一个简单的自写存储库的 bean，该存储库仅持续存在内存中集合中的对象。

由于它的 id 是 questionRepository Spring 尝试在 QuestionServiceImpl 类的 questionRepository 字段中按名称 Autowiring 它。

长话短说:仔细检查其他人可能在您的配置文件中定义的名称。 :)

关于java - Spring Data Repository Autowiring 失败，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/9512177/

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