Java 事务不活跃 - Hibernate - JPA
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/20096856/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Transaction not active - Hibernate - JPA
提问by Houssem Badri
I have this class which is dedicated to persist data in db through persistance layer of hibernate.
我有这个类专门用于通过休眠的持久层将数据持久化到数据库中。
public class TLinkEquipementDAOImpl implements TLinkEquipementDAO {
private static final Log log = LogFactory
.getLog(TLinkEquipementDAOImpl.class);
@PersistenceContext
private EntityManagerFactory emf = PersistenceManager.getInstance()
.getEntityManagerFactory();
private EntityManager entityManager = emf.createEntityManager();
private EntityTransaction tx = entityManager.getTransaction();
public void persist(TLinkEquipement transientInstance) {
log.debug("persisting TLinkEquipement instance");
try {
tx.begin();
entityManager.persist(transientInstance);
tx.commit();
log.debug("persist successful");
} catch (RuntimeException re) {
tx.rollback();
log.error("persist failed", re);
throw re;
}
}
//Staff
}
The problem is that it does not persist data.
问题是它不持久化数据。
The stack is:
堆栈是：
Exception in thread "main" java.lang.IllegalStateException: Transaction not active
at org.hibernate.ejb.TransactionImpl.rollback(TransactionImpl.java:82)
at sau.se.domain.dao.Impl.TLinkEquipementDAOImpl.persist(TLinkEquipementDAOImpl.java:47)
at sau.se.domain.service.Impl.TLinkEquipementServiceImpl.persist(TLinkEquipementServiceImpl.java:29)
at sau.se.extractor.InfoExtract.getAllSPData(InfoExtract.java:346)
at sau.se.extractor.InfoExtract.main(InfoExtract.java:436)
But i have to note, that it works fine in other classes.
但我必须注意，它在其他课程中工作正常。
UPDATE:
更新：
when i make print of tx.isActive()it gives me false.
当我打印tx.isActive()它给我false。
UPDATE
更新
I tried to more get some info about the error:
我试图更多地获取有关错误的一些信息：
I got where the problem is:
我知道问题出在哪里：
Caused by: org.hibernate.TransientObjectException: object references an unsaved transient instance - save the transient instance before flushing: sau.se.domain.model.TLinkEquipement.TEquipementsByIdEquipement2 -> sau.se.domain.model.TEquipements
at org.hibernate.engine.CascadingAction.noCascade(CascadingAction.java:376)
in fact, the table TLinkEquipementhas 2 fk to the same table TEquipements, and me, i persist data of TEquipementsthen those of TLinkEquipement
实际上，该表TLinkEquipement有 2 个 fk 到同一个表TEquipements，而我，我保留了TEquipements当时的数据TLinkEquipement
采纳答案by rzymek
Probably tx.begin()threw an exception. That means that in the catchclause there was no active transaction to rollback. That's why tx.rollback()threw another exception (shadowing the original error).
可能tx.begin()抛出异常。这意味着在catch子句中没有要回滚的活动事务。这就是为什么tx.rollback()抛出另一个异常（隐藏原始错误）。
To see the source exception rewrite your catchblock:
要查看源异常重写您的catch块：
} catch (RuntimeException re) {
log.error("persist failed", re); //moved to top
tx.rollback();
throw re;
}
Also not that you're mixing concepts here. On one hand you're declaring injected entity manager (@PersistenceContext), on the other hand you're creating using EntityManagerFactoryprogrammatically.
也不是说你在这里混合概念。一方面，您正在声明注入的实体管理器 ( @PersistenceContext)，另一方面，您正在以EntityManagerFactory编程方式创建 using 。
If this is a JEE bean, it should look like this:
如果这是一个 JEE bean，它应该是这样的：
@Stateless
public class TLinkEquipementDAOImpl implements TLinkEquipementDAO {
private static final Log log = LogFactory.getLog(TLinkEquipementDAOImpl.class);
@PersistenceContext
private EntityManager entityManager;
public void persist(TLinkEquipement transientInstance) {
log.debug("persisting TLinkEquipement instance");
entityManager.persist(transientInstance);
log.debug("persist successful");
}
//Staff
}
Here transaction management and entity manager management is handled by the container (application server).
这里事务管理和实体管理器管理由容器（应用服务器）处理。
If this class is used outside of a container then I could look like this:
如果这个类在容器之外使用，那么我可能看起来像这样：
public class TLinkEquipementDAOImpl implements TLinkEquipementDAO {
private static final Log log = LogFactory.getLog(TLinkEquipementDAOImpl.class);
//I'm assuming getEntityManagerFactory() returnes an already created EMF
private EntityManagerFactory emf = PersistenceManager.getInstance()
.getEntityManagerFactory();
private EntityManager entityManager = emf.createEntityManager();
public void persist(TLinkEquipement transientInstance) {
EntityTransaction tx = entityManager.getTransaction();
log.debug("persisting TLinkEquipement instance");
try {
tx.begin();
entityManager.persist(transientInstance);
tx.commit();
log.debug("persist successful");
} catch (RuntimeException re) {
log.error("persist failed", re);
if(tx.isActive()) {
tx.rollback();
}
throw re;
}
}
//Staff
}
回答by joshpt
For others who may get this error messsage: "Exception in thread "main" java.lang.IllegalStateException: Transaction not active"
对于可能收到此错误消息的其他人：“线程“main”中的异常 java.lang.IllegalStateException: Transaction not active”
Check your merge operation. You may be trying to merge an object that is supposed to be a reference instead of an object you just created. By reference, I mean... you need to have a live reference to that object from the database... hence the "transaction not active" error message.
检查您的合并操作。您可能正在尝试合并一个应该是引用的对象，而不是您刚刚创建的对象。通过引用，我的意思是...您需要从数据库中对该对象进行实时引用...因此会出现“事务未激活”错误消息。
Here is an example piece of code for querying an object from the database with JPQL:
下面是一段使用 JPQL 从数据库中查询对象的示例代码：
public static Users getUserByName(EntityManager em, String name) throws NoResultException, Exception {
Users user = null;
user = em.createQuery("SELECT u from Users u WHERE u.name =:name", Users.class).setParameter("name", name).setMaxResults(1).getSingleResult();
return user;
}
回答by HeyLink
I just came across this problem, and now I had solved it. But I realize that I was so stupid.
我刚刚遇到这个问题，现在我已经解决了。但我发现我太愚蠢了。
the reason I find is that the data I want to commit has a foreign key but I forget that, so the transaction will always close itself. I add the foreign key in the database, and then the test or main method run successfully.
我发现的原因是我想提交的数据有一个外键，但我忘记了，所以事务总是会自行关闭。我在数据库中添加了外键，然后test或者main方法就运行成功了。
the Key point I want to say is that please write this in your code.
我想说的关键点是请在您的代码中写下这个。
} catch (Exception ex) {
ex.printStackTrace();
tx.rollback();}
and you will easily find the reason why the transaction closed or not alive. that is my experience,hope useful!
你会很容易找到交易关闭或不活跃的原因。这是我的经验，希望有用！
回答by Antonio Petricca
I am using Hibernate 5.3.1.Finalwith Weblogic 12.2.1.2, and I solved the issue by the following persistence.xmlconfiguration:
我正在使用Hibernate 5.3.1.Final和Weblogic 12.2.1.2，我通过以下persistence.xml配置解决了这个问题：
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" 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">
<persistence-unit name="mainPU" transaction-type="JTA">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<jta-data-source>${wls.datasource}</jta-data-source>
<properties>
<property name="hibernate.show_sql" value="true"/>
<property name="hibernate.format_sql" value="true"/>
<property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect"/>
<!-- https://issues.jboss.org/browse/FORGE-621?_sscc=t -->
<property name="hibernate.transaction.jta.platform" value="org.hibernate.engine.transaction.jta.platform.internal.WeblogicJtaPlatform" />
</properties>
</persistence-unit>
</persistence>
