当前位置: 首页 > 面试题库 >

Spring @Transactional方法中没有事务开始

蒋高超
2023-03-14
问题内容

使用Spring(3.0.5),Hibernate(3.6.0)和Wicket(1.4.14)开发应用程序时遇到了一个奇怪的问题。问题是:我无法将任何对象保存或修改到数据库中。“不能”是指对象的所有更改或对EntityManager.persist(foo)的调用都被简单,无声地忽略。选择工作。

示例案例很简单-在某些检票页面上,我尝试将对象保存到数据库中,如下所示

public class ComicDetailsPage extends PublicBasePage {

@Override
protected void onConfigure() {
    System.out.println("In onConfigure");
    super.onConfigure();
    comicDAO.insert("abc");

}

@SpringBean(name="comicDAO")
private ComicDAO comicDAO;

    (....)

这是comicDAO

@Service
public class ComicDAO {

@PersistenceContext
private EntityManager em;

(...)

@Transactional
public void insert(String title) {
    Comic c = new Comic();
    c.setTitle(title);
    em.persist(c);
}

@Transactional
public Comic add1toTitle(int pk) {
    System.out.println("Beginning fetching");
    Comic c = em.find(Comic.class, pk);
    System.out.println("Fetched updating");
    c.setTitle(c.getTitle()+"1");
    System.out.println("Updated persisting");
    em.persist(c);
    System.out.println("Persisted returning");
    return c;
}

我打开了日志记录,这是日志的相关部分(Hibernate和Spring都设置为TRACE)。我在我认为很重要的行中添加了**。

In onConfigure
01:53:19.330 [qtp2119047503-15] DEBUG o.s.beans.factory.support.DefaultListableBeanFactory - Returning cached instance of singleton bean 'txManager'
**01:53:19.330 [qtp2119047503-15] DEBUG org.hibernate.impl.SessionImpl - opened session at timestamp: 13006687993**
**01:53:19.330 [qtp2119047503-15] DEBUG org.hibernate.transaction.JDBCTransaction - begin**
01:53:19.330 [qtp2119047503-15] DEBUG org.hibernate.jdbc.ConnectionManager - opening JDBC connection
01:53:19.335 [qtp2119047503-15] DEBUG org.hibernate.transaction.JDBCTransaction - current autocommit status: true
01:53:19.335 [qtp2119047503-15] DEBUG org.hibernate.transaction.JDBCTransaction - disabling autocommit
01:53:19.336 [qtp2119047503-15] TRACE org.hibernate.jdbc.JDBCContext - after transaction begin
01:53:19.336 [qtp2119047503-15] DEBUG org.hibernate.impl.SessionImpl - opened session at timestamp: 13006687993
01:53:19.336 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - setting flush mode to: AUTO
01:53:19.336 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - setting cache mode to: NORMAL
01:53:19.337 [qtp2119047503-15] TRACE org.hibernate.engine.IdentifierValue - id unsaved-value: 0
01:53:19.337 [qtp2119047503-15] TRACE org.hibernate.event.def.AbstractSaveEventListener - transient instance of: pl.m4ks.comics.entity.Comic
01:53:19.337 [qtp2119047503-15] TRACE org.hibernate.event.def.DefaultPersistEventListener - saving transient instance
**01:53:19.338 [qtp2119047503-15] TRACE org.hibernate.event.def.AbstractSaveEventListener - saving [pl.m4ks.comics.entity.Comic#<null>]**
**01:53:19.341 [qtp2119047503-15] DEBUG org.hibernate.event.def.AbstractSaveEventListener - delaying identity-insert due to no transaction in progress**
01:53:19.341 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - closing session
01:53:19.341 [qtp2119047503-15] TRACE org.hibernate.jdbc.ConnectionManager - connection already null in cleanup : no action
01:53:19.341 [qtp2119047503-15] DEBUG org.hibernate.transaction.JDBCTransaction - commit
**01:53:19.341 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - automatically flushing session**
01:53:19.341 [qtp2119047503-15] TRACE org.hibernate.jdbc.JDBCContext - before transaction completion
01:53:19.341 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - before transaction completion
01:53:19.342 [qtp2119047503-15] DEBUG org.hibernate.transaction.JDBCTransaction - re-enabling autocommit
01:53:19.342 [qtp2119047503-15] DEBUG org.hibernate.transaction.JDBCTransaction - committed JDBC Connection
01:53:19.342 [qtp2119047503-15] TRACE org.hibernate.jdbc.JDBCContext - after transaction completion
01:53:19.342 [qtp2119047503-15] DEBUG org.hibernate.jdbc.ConnectionManager - transaction completed on session with on_close connection release mode; be sure to close the session to release JDBC resources!
01:53:19.342 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - after transaction completion
01:53:19.342 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - closing session
01:53:19.342 [qtp2119047503-15] TRACE org.hibernate.jdbc.ConnectionManager - performing cleanup
01:53:19.342 [qtp2119047503-15] DEBUG org.hibernate.jdbc.ConnectionManager - releasing JDBC connection [ (open PreparedStatements: 0, globally: 0) (open ResultSets: 0, globally: 0)]
01:53:19.342 [qtp2119047503-15] TRACE org.hibernate.jdbc.JDBCContext - after transaction completion
01:53:19.342 [qtp2119047503-15] DEBUG org.hibernate.jdbc.ConnectionManager - transaction completed on session with on_close connection release mode; be sure to close the session to release JDBC resources!
01:53:19.342 [qtp2119047503-15] TRACE org.hibernate.impl.SessionImpl - after transaction completion

当然,没有对象被保存到数据库中。

最后一个文件-我的应用程序COntext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans (...)>

    <context:component-scan base-package="pl.m4ks.comics"/>
    <context:annotation-config />

    <bean id="dataSource" class="org.springframework.jdbc.datasource.SimpleDriverDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:8889/comics" />
        <property name="username" value="root"/>
        <property name="password" value="root" />          
    </bean>

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

    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
         <property name="dataSource">
            <ref bean="dataSource"/>
        </property>
        <property name="packagesToScan">
             <value>pl.m4ks.comics</value>
        </property>
    </bean>


    <bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory">
            <ref bean="sessionFactory" />
        </property>
    </bean>

    <bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />

    <tx:annotation-driven transaction-manager="txManager"  proxy-target-class="true"/>
</beans>

我不知道可能是什么问题以及如何解决。我不想在我的代码中管理事务-这就是Spring的目的。


问题答案:

a)您正在定义Hibernate SessionFactory和JPA
EntitymanagerFactory。会是什么?使用Hibernate作为提供程序的Hibernate的Session
API或JPA的Entitymanager API,但不能两者都使用。

b)您已经定义了一个HibernateTransactionManager,但是由于您EntityManager在代码中使用,因此需要一个JpaTransactionManager

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

这是applicationContext.xml的注释版本:

<?xml version="1.0" encoding="UTF-8"?>
<beans (...)>

    <context:component-scan base-package="pl.m4ks.comics"/>
    <context:annotation-config />

    <bean id="dataSource" 
    class="org.springframework.jdbc.datasource.SimpleDriverDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:8889/comics" />
        <property name="username" value="root"/>
        <property name="password" value="root" />          
    </bean>

    <!-- use either this: -->
    <bean id="entityManagerFactory"
    class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="persistenceUnitName" value="main" />
        <property name="dataSource" ref="dataSource" />
    </bean>

    <!-- or this -->
    <bean id="sessionFactory"
    class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
         <property name="dataSource">
            <ref bean="dataSource"/>
        </property>
        <property name="packagesToScan">
             <value>pl.m4ks.comics</value>
        </property>
    </bean>
    <!-- (but not both) -->

    <!-- this is correct for AnnotationSessionFactoryBean, but not if you use
         LocalContainerEntityManagerFactoryBean --> 
    <bean id="txManager" 
    class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory">
            <ref bean="sessionFactory" />
        </property>
    </bean>

    <!-- not necessary, <context:annotation-config /> automatically includes this -->
    <bean 
    class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />

    <tx:annotation-driven transaction-manager="txManager" proxy-target-class="true"/>
</beans>

还有一个设计说明: DAO不应是事务性的。您应该使用管理事务的服务层。



 类似资料:
  • 问题内容: 我正在使用Spring注释来管理我的事务,如下所示: 我想知道如果忘记注释会发生什么: 当alertDAO实现如下时: 似乎Hibernate允许我从数据库中获取数据,即使没有注释也是如此。 这种粗心大意的后果是什么?可能发生的最坏情况是什么? 问题答案: 根据文档(Spring docs ),它仅仅是元数据,它表明方法或接口可以由“具有交易意识的”事物(例如)进行配置。 相信只有 t

  • 我正在查看一些现有的代码,并想知道在下面的场景中使用Spring的@Transactional注释会发生什么?考虑以下示例: 下面的updateDataBaseItem()方法是常见的,可以从其他非事务性方法和上面的方法调用:

  • 嗯,在这个问题上我可能是错的,但是我需要你的宝贵意见/建议来站在正确的道路上。 我想知道在和中处理事务管理的好的、更好的、最好的方法,以及每种方法的优缺点。 我知道的一些方案/方法也是如此: 1) 使用AOP注释的Spring事务管理(,,带有诸如,,等建议)。 问题1:我之前用SpringAOP做了一个日志示例,但我不知道如何在事务管理中做同样的事情。事务是否会在该方面类中启动、回滚和提交,并提

  • 问题内容: 我在Service类中看到了一种被标记为的方法,但是它也在同一类中调用了其他未标为的方法。 这是否意味着对单独方法的调用导致应用程序打开与DB的单独连接或暂停父事务等? 不带任何注释的方法的默认行为是什么,而另一个带有注释的方法调用该方法的默认行为是什么? 问题答案: 当你调用没有事务块之内的方法时,父事务将继续使用新方法。它将使用与父方法(with )相同的连接,以及在调用的方法中导