Java Hibernate:无法访问TransactionManager或UserTransaction以进行物理事务委托

我使用Servlets、PostgreSQL和Hibernate以及EntityManager构建了一个Web应用程序，在我将项目转移到基于Maven的项目之前，一切都正常。现在，每当我尝试从EntityManager工厂创建EntityManager时，我都会遇到一个奇怪的异常：

org.hibernate.resource.transaction.backend.jta.internal.JtaPlatformInaccessibleException: Unable to access TransactionManager or UserTransaction to make physical transaction delegate
at org.hibernate.resource.transaction.backend.jta.internal.JtaTransactionCoordinatorImpl.makePhysicalTransactionDelegate(JtaTransactionCoordinatorImpl.java:229)
at org.hibernate.resource.transaction.backend.jta.internal.JtaTransactionCoordinatorImpl.getTransactionDriverControl(JtaTransactionCoordinatorImpl.java:203)
at org.hibernate.engine.transaction.internal.TransactionImpl.<init>(TransactionImpl.java:36)
at org.hibernate.internal.AbstractSessionImpl.getTransaction(AbstractSessionImpl.java:309)
at org.hibernate.internal.SessionImpl.<init>(SessionImpl.java:277)
at org.hibernate.internal.SessionFactoryImpl$SessionBuilderImpl.openSession(SessionFactoryImpl.java:1322)
at org.hibernate.jpa.internal.EntityManagerImpl.internalGetSession(EntityManagerImpl.java:133)
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.postInit(AbstractEntityManagerImpl.java:174)
at org.hibernate.jpa.internal.EntityManagerImpl.<init>(EntityManagerImpl.java:83)
at org.hibernate.jpa.internal.EntityManagerFactoryImpl.internalCreateEntityManager(EntityManagerFactoryImpl.java:311)
at org.hibernate.jpa.internal.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:278)
at cl.bicubic.App.getEntityManager(App.java:100)
at cl.bicubic.dao.DAO.<init>(DAO.java:24)
at cl.bicubic.dao.UserAtomicDAO.<init>(UserAtomicDAO.java:15)
at cl.bicubic.Application.init(Application.java:70)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1241)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1154)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:827)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:136)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:526)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:655)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:222)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1566)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1523)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

我使用ServletContextListener调用此方法

@WebListener
public class ApplicationServletContextListener implements ServletContextListener {

    @Override
    public void contextInitialized(ServletContextEvent sce) {
        try {
            App.setServletContext(sce.getServletContext());
        } catch (Exception ex) {
           Logger.getLogger(ApplicationServletContextListener.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    ...

}

这就是我尝试创建EntityManager的方式

public class DAO {
    ...
    protected EntityManager entityManager;
    ...
    public DAO() {
        entityManager = App.getEntityManager();
        ...
    }

    ...
}

---

我试图寻找关于这个JtaPlatformInaccessibleException的起源的更多信息，但我什么也没找到。我不确定缺少了什么。

向DAO和访问DAO类的类添加

@Transactional

请参阅：

好的。。。

---

这只是持久性单元xml配置上的一个错误，我从持久性单元标记中删除了transaction type=“JTA”。它似乎是由IDE自动添加的。

只需将属性添加到persistence.xml中即可

<property name="hibernate.transaction.jta.platform" value="org.hibernate.service.jta.platform.internal.SunOneJtaPlatform"/>

我没有使用Spring。。。只是一个简单的HttpServlet。我试图添加@Transactional，但什么也没做。@Transactional是JPA javax.transaction.TransactionalYeap的一部分，我知道。。。我把它加上去了。。我使用Hibernate 5.0.1.Final和PostgreSQL驱动程序9.2-1002-JDBC4这是一个适合我的解决方案。原始海报的解决方案在我的案例中不起作用。在Wildfly 10.0.0.0.Final上使用Hibernate 5.0.7，我需要在persistence.xml中包含以下行：。。。根据文档，

JTA

是

交易类型的默认值。不管你是定义它还是完全忽略它，它都应该没有区别。
public class DAO {
    ...
    protected EntityManager entityManager;
    ...
    public DAO() {
        entityManager = App.getEntityManager();
        ...
    }

    ...
}

<property name="hibernate.transaction.jta.platform" value="org.hibernate.service.jta.platform.internal.SunOneJtaPlatform"/>