Spring JPA 存储库 Autowiring 问题

Question

我按照 youtube 视频教程设置 Spring JPA 项目，但我的 Spring JPA 项目仍然有问题，希望有人能提供帮助。

http://www.youtube.com/watch?v=kM7Gr3XTzIg

主要问题似乎是 Autowiring 我的 JPARepository。我已经通过以下测试代码测试了我的 entityManager/持久性单元是否工作(它拉回了预期的记录)。

public class CheckEntityManagerWorksTest {
    private static Logger logger = Logger.getLogger(CheckEntityManagerWorksTest.class.getName());

    private static EntityManagerFactory emFactory;

    private static EntityManager em;

    @BeforeClass
    public static void setUp() throws Exception {
        try {
            logger.info("Building JPA EntityManager for unit tests");
            emFactory = Persistence.createEntityManagerFactory("pu");
            em = emFactory.createEntityManager();
        } catch (Exception ex) {
            ex.printStackTrace();
            fail("Exception during JPA EntityManager instanciation.");
        }
    }

    @AfterClass
    public static void tearDown() throws Exception {
        logger.info("Shuting down Hibernate JPA layer.");
        if (em != null) {
            em.close();
        }
        if (emFactory != null) {
            emFactory.close();
        }
    }

    @Test
    public void testPersistence() {
        try {

            em.getTransaction().begin();

            Integer id = 51;
            Accounts account = em.find(Accounts.class, id);
            assertNotNull(account);

            System.out.println("Account username: " + account.getUsername());

            em.getTransaction().commit();

        } catch (Exception ex) {
            em.getTransaction().rollback();
            ex.printStackTrace();
            fail("Exception during testPersistence");
        }
    }
}

正如我所说，该测试适用于连接到数据库等，但下面的测试因 Autowiring 异常而失败(页面最底部的堆栈跟踪):

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("**/applicationContext.xml")
public class AccountsRepositoryTest {

    @Autowired
    AccountsRepository repo;

    @Test
    public void testAccountsRepository() {
        assertNotNull(repo.findOne(51));
    }
}

下面是我的设置。

持久性.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence     http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
             version="2.0">
    <persistence-unit name="pu">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <properties>
            <property name="hibernate.connection.url" value="jdbc:derby://localhost:1527/craigtest"/>
            <property name="hibernate.connection.password" value="craigtest"/>
            <property name="hibernate.connection.driver_class" value="org.apache.derby.jdbc.ClientDriver"/>
            <property name="hibernate.connection.username" value="craigtest"/>
            <property name="hibernate.dialect" value="org.hibernate.dialect.DerbyDialect" />
            <property name="hibernate.show_sql" value="true" />
        </properties>
    </persistence-unit>
</persistence>

ApplicationContext.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"
       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">

    <bean id="myEmf" class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
        <property name="persistenceUnitName" value="pu"/>
    </bean>

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

    <jpa:repositories base-package="com.mycompany.jpaspring.repositories" />
</beans>

我的仓库:

package com.mycompany.jpaspring.repositories;

import com.mycompany.jpaspring.entity.Accounts;
import org.springframework.data.jpa.repository.JpaRepository;

public interface AccountsRepository extends JpaRepository<Accounts, Integer>{

}

我的实体:

package com.mycompany.jpaspring.entity;

import java.io.Serializable;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.xml.bind.annotation.XmlRootElement;
@Entity
@Table(name = "ACCOUNTS")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Accounts.findAll", query = "SELECT a FROM Accounts a"),
    @NamedQuery(name = "Accounts.findById", query = "SELECT a FROM Accounts a WHERE a.id = :id"),
    @NamedQuery(name = "Accounts.findByUsername", query = "SELECT a FROM Accounts a WHERE a.username = :username"),
    @NamedQuery(name = "Accounts.findByFirstname", query = "SELECT a FROM Accounts a WHERE a.firstname = :firstname"),
    @NamedQuery(name = "Accounts.findByLastname", query = "SELECT a FROM Accounts a WHERE a.lastname = :lastname")})
public class Accounts implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @Basic(optional = false)
    @Column(name = "ID")
    private Integer id;
    @Basic(optional = false)
    @Column(name = "USERNAME")
    private String username;
    @Column(name = "FIRSTNAME")
    private String firstname;
    @Column(name = "LASTNAME")
    private String lastname;

    public Accounts() {
    }

    public Accounts(Integer id) {
        this.id = id;
    }

    public Accounts(Integer id, String username) {
        this.id = id;
        this.username = username;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getFirstname() {
        return firstname;
    }

    public void setFirstname(String firstname) {
        this.firstname = firstname;
    }

    public String getLastname() {
        return lastname;
    }

    public void setLastname(String lastname) {
        this.lastname = lastname;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof Accounts)) {
            return false;
        }
        Accounts other = (Accounts) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "com.mycompany.jpaspring.entity.Accounts[ id=" + id + " ]";
    }

}

堆栈跟踪:

-------------------------------------------------------------------------------
Test set: com.mycompany.jpaspring.AccountsRepositoryTest
-------------------------------------------------------------------------------
Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.797 sec <<< FAILURE!
testAccountsRepository(com.mycompany.jpaspring.AccountsRepositoryTest)  Time elapsed: 0.507 sec  <<< ERROR!
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.mycompany.jpaspring.AccountsRepositoryTest': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.mycompany.jpaspring.repositories.AccountsRepository com.mycompany.jpaspring.AccountsRepositoryTest.repo; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.mycompany.jpaspring.repositories.AccountsRepository] 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:287)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1106)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:374)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:110)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:75)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:312)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:211)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:288)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:284)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:88)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174)
    at org.apache.maven.surefire.junit4.JUnit4TestSet.execute(JUnit4TestSet.java:53)
    at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:123)
    at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:104)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:164)
    at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:110)
    at org.apache.maven.surefire.booter.SurefireStarter.invokeProvider(SurefireStarter.java:175)
    at org.apache.maven.surefire.booter.SurefireStarter.runSuitesInProcessWhenForked(SurefireStarter.java:107)
    at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:68)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.mycompany.jpaspring.repositories.AccountsRepository com.mycompany.jpaspring.AccountsRepositoryTest.repo; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.mycompany.jpaspring.repositories.AccountsRepository] 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$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:513)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:92)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:284)
    ... 32 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.mycompany.jpaspring.repositories.AccountsRepository] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:947)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:816)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:730)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:485)
    ... 34 more

Answer 1

对我来说一切似乎都很好，除了这一行:

@ContextConfiguration("**/applicationContext.xml")

你真的需要导入多个xml文件吗？applicationContext.xml 到底在哪个文件夹中？您可以尝试用完整路径引用替换上面的内容吗？像这样:

@ContextConfiguration("classpath:/com/.../application-context.xml")