如果没有活动事务 - 休眠，保存无效

Question

我在将条目保存到postgres DB时遇到了一些问题。我正在使用休眠和弹簧，但我无法为此目的使用 DAO 类。相反，以下代码对我有用：

Session session = sessionFactory.openSession();
    Transaction tx = null;
    Blob blob = null;
    try {
        tx = session.beginTransaction();
        VoiceMail message02 = new VoiceMail(44, 1, "dir/msgs",
                "dummy_data", "dummy_data", "6003", "19/01/2015",
                "1:35", "flag", "dummy_data", "dummy_data", blob,
                "label", false, "1");
        //voiceMailDao.save(message02);
        session.save(message02);
        tx.commit();
    } catch (HibernateException e) {
        if (tx != null)
            tx.rollback();
        e.printStackTrace();
    } finally {
        session.close();
    }

当我尝试评论该行时

session.save(message02);

并离开线路

voiceMailDao.save(message02);

它不起作用。将生成以下输出：

save is not valid without active transaction
at org.hibernate.context.internal.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:352)
at com.sun.proxy.$Proxy750.save(Unknown Source)
at com.musala.ving.daoimpl.VoiceMailDaoImpl.save(VoiceMailDaoImpl.java:17)
at com.musala.ving.controllers.VoiceMailController.list(VoiceMailController.java:52)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:175)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:446)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:434)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)

很抱歉这篇文章很长，但我在这里阅读了有关此问题的所有主题，但我仍然无法弄清楚。

我的DAO类如下：

public class VoiceMailDaoImpl  implements VoiceMailDao{
@Autowired
private SessionFactory sessionFactory;
public void save(VoiceMail voicemail) {
    this.sessionFactory.getCurrentSession().save(voicemail);
}
public void update(VoiceMail voicemail) {
    this.sessionFactory.getCurrentSession().update(voicemail);
}
public void delete(VoiceMail voicemail) {
    this.sessionFactory.getCurrentSession().delete(voicemail);
}

}

任何帮助不胜感激！

谢谢！

Answer 1

你能只使用注释吗？

它要容易得多，只需使用事务性注释您的 dao 类即可。

@Transactional

然后所有方法都是自动事务性的，如果你只想要它用于特定方法，你也可以将相同的注释添加到方法本身。它需要处理交易的麻烦。

有关如何实现此目的的良好示例，请参阅此链接。

----编辑----

此外，如果你足够早地进入你的项目，看看spring-boot，它会大大加快你的系统开发速度。弹簧 - 启动。该项目有助于使用一些最佳实践设置您的系统，并让您更快地运行。我们目前正在新项目中使用它，这使得建立新项目的速度非常快。