带有Spring的java EclipseLink无法持久保存到Db中

Question

我正在使用Spring+EclipseLink 2管理Derby数据库上的实体。从db中选择对象工作得很好，但当我尝试持久化一个对象时，什么也没发生。程序正确执行，不会引发异常。我可能做错了什么，因为我不熟悉Spring，谢谢您的评论和建议：）

ServerDaoDb方法：

@Transactional
public void addServer(Server server) {
    EntityManager em = emf.createEntityManager();
    emf.createEntityManager().persist(server);
    em.close();
}

应用程序上下文是：

 ... 
 <tx:annotation-driven />

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

    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>
<bean 
class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />
<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>

坚持。xml:

  <persistence-unit name="SpringPratiquePU" transaction-type="RESOURCE_LOCAL">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <class>net.athom.spring.examples.models.eas.Server</class>
    <class>net.athom.spring.examples.models.eas.Node</class>
    <properties>
      <property name="eclipselink.target-database" value="DERBY"/>
      <property name="javax.persistence.jdbc.url" value="jdbc:derby://localhost:1527/SpringPratique"/>
      <property name="javax.persistence.jdbc.password" value="clem"/>
      <property name="javax.persistence.jdbc.driver" value="org.apache.derby.jdbc.ClientDriver"/>
      <property name="javax.persistence.jdbc.user" value="clem"/>
    </properties>
  </persistence-unit>
</persistence>

调试跟踪：

DEBUG JpaTransactionManager:365 - Creating new transaction with name [net.athom.spring.examples.service.impl.ServerManagerImpl.addServer]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT; ''
[EL Info]: 2010-10-29 15:33:27.443--ServerSession(14894886)--EclipseLink, version: Eclipse Persistence Services - 2.0.2.v20100323-r6872
[EL Info]: 2010-10-29 15:33:28.606--ServerSession(14894886)--file:/C:/netbeanProject/SpringPratique/src/_SpringPratiquePU login successful
15:33:28,893       DEBUG JpaTransactionManager:323 - Opened new EntityManager [org.eclipse.persistence.internal.jpa.EntityManagerImpl@1779885] for JPA transaction
15:33:28,951       DEBUG DefaultListableBeanFactory:242 - Returning cached instance of singleton bean 'transactionManager'
15:33:28,952       DEBUG JpaTransactionManager:286 - Found thread-bound EntityManager [org.eclipse.persistence.internal.jpa.EntityManagerImpl@1779885] for JPA transaction
15:33:28,953       DEBUG JpaTransactionManager:470 - Participating in existing transaction
15:33:29,266       DEBUG JpaTransactionManager:752 - Initiating transaction commit
15:33:29,267       DEBUG JpaTransactionManager:462 - Committing JPA transaction on EntityManager [org.eclipse.persistence.internal.jpa.EntityManagerImpl@1779885]
15:33:29,268       DEBUG JpaTransactionManager:548 - Closing JPA EntityManager [org.eclipse.persistence.internal.jpa.EntityManagerImpl@1779885] after transaction
15:33:29,308       DEBUG EntityManagerFactoryUtils:328 - Closing JPA EntityManager

Answer 1

谢谢你的回答，两个都很有帮助。我最终使用了LocalContainerEntityManagerFactoryBean，这样就可以将实体管理器注入到我的dao中。 我添加了servlet-agent-2.5.6。lib文件夹上的jar和pass VM选项： -javaagent:path/to/lib/ervlet-agent-2.5.6。罐子

然后我修改了ApplicationContext。xml:

 <bean id="entityManagerFactory"
        class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="persistenceUnitName" value="SpringPratiquePU" />
         <property name="loadTimeWeaver">
<bean class="org.springframework.instrument.classloading.InstrumentationLoadTimeWeaver" />
    </property>
    </bean>

还有我的刀： ...

  @PersistenceContext
  private EntityManager em;


   @Transactional
   public void addServer(Server server) {
       em.persist(server);
   }

坚持和交易现在很有魅力

Answer 2

你的错误在这里：

@Transactional
public void addServer(Server server) {
    EntityManager em = emf.createEntityManager();
    emf.createEntityManager().persist(server);
    em.close();
}

您正在创建两个不同的EntityManager实例，一个是正在关闭的em，另一个是位于下一行的emf.createEntityManager()的新实例，您直接使用它来保存更改

试试这个：

@Transactional
public void addServer(Server server) {
    EntityManager em = emf.createEntityManager();
    em.persist(server);
    em.close();
}

我猜，当您关闭em实例时，您的更改会写入DB，但如果没有写入，您必须在关闭em实例之前添加em.flush();

Answer 3

我不确定您的配置到底出了什么问题（我猜手动创建的EntityManager不能参与@Transactional事务），但Spring中典型的JPA配置是这样的，所以您不需要手动创建EntityManager（还要注意工厂bean的类名）：

@PersistenceContext
private EntityManager em;

@Transactional  
public void addServer(Server server) {  
    em.persist(server);  
} 

---

<bean id="entityManagerFactory"   
    class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">   
    <property name="persistenceUnitName" value="SpringPratiquePU" />   
</bean>