Hibernate 休眠会话关闭问题!
下面的函数是我在web应用程序中的一个按钮的actionListener,我正在从数据库中的表中删除旧的选定行,并将新行插入数据库Hibernate 休眠会话关闭问题!,hibernate,session,jsf,hql,Hibernate,Session,Jsf,Hql,下面的函数是我在web应用程序中的一个按钮的actionListener,我正在从数据库中的表中删除旧的选定行,并将新行插入数据库 public void getSelectedExemptionItems(ActionEvent ae) { Session hibernateSession; Session hibernate2Session; selectedExemptions = new ArrayList<ExemptionBean
public void getSelectedExemptionItems(ActionEvent ae) {
Session hibernateSession;
Session hibernate2Session;
selectedExemptions = new ArrayList<ExemptionBean>();
for (ExemptionBean eBean : exemBean) { // iterating over the list of ExemptionBean class
if (selectedExemptionIDs.get(eBean.getExemptionID()).booleanValue()) {
selectedExemptions.add(eBean); // adding every ExemptionBean that is selected.
}
}
// getting importane session variables
SessionBean1 theSessionBean = (SessionBean1) FacesContext.getCurrentInstance().getExternalContext().getSessionMap().get("SessionBean1");
JAdmApplication admApplication = theSessionBean.getAdmApplication();
long admAppID = admApplication.getJAdmApplicationId();
// ArrayList<JAdmAppExemption> admAppExemption = (ArrayList<JAdmAppExemption>)theSessionBean.getAdmAppExemption();
JAdmAppExemption admAppExem = new JAdmAppExemption();
// try catch : delete all previously chosen exemptions from database by logged-in user.
try {
hibernateSession = HibernateUtil.getAdmSessionFactory().getCurrentSession();
Transaction t = hibernateSession.beginTransaction();
t.begin();
String sequel = "DELETE FROM JAdmAppExemption WHERE createdby = ?";
Query q = hibernateSession.createQuery(sequel);
q.setParameter(0, theSessionBean.getPortalUserId());
} catch (Exception e){
System.out.println("Row could not be deledted from database!!");
}
// adding all selected exemptions to the database
for (ExemptionBean e : selectedExemptions) {
admAppExem.setAdClientId(1000001);
admAppExem.setAdOrgId(1000001);
admAppExem.setCreated(getTimestamp());
admAppExem.setCreatedby(theSessionBean.getPortalUserId());
admAppExem.setIsactive('Y');
admAppExem.setJAdmAppExemptionId(getJAdmAppExemptionIdSequence());
admAppExem.setJAdmApplicationId(admAppID);
admAppExem.setJAdmExemptionId(e.getExemptionID());
admAppExem.setUpdated(getTimestamp());
admAppExem.setUpdatedby(theSessionBean.getPortalUserId());
hibernate2Session = HibernateUtil.getAdmSessionFactory().getCurrentSession(); // session is opened here!
Transaction tx = hibernate2Session.beginTransaction();
tx.begin();
try {
hibernate2Session.beginTransaction();
hibernate2Session.save(admAppExem); // is it save or saveOrUpdate??
hibernate2Session.getTransaction().commit();
updateJAdmAppExemptionIdSequence();
} catch (Throwable ex){
if (hibernate2Session.getTransaction().isActive()) {
hibernate2Session.getTransaction().rollback();
}
ex.printStackTrace();
}
}
}
谢谢,您在会话范围的托管bean中使用了惰性抓取,而Hibernate会话显然配置为基于请求
长话短说:。如果有人在Hibernate中遇到这个问题,我会找到一个简洁的答案。显然很简单 在hibernate中使用托管会话简化单元测试2006年11月6日 如果您曾经尝试在Hibernate中重用会话,您可能会遇到此异常
org.hibernate.SessionException: Session is closed!
at org.hibernate.impl.AbstractSessionImpl.errorIfClosed(AbstractSessionImpl.java:49)
at org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1319)
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.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:301)
at $Proxy0.beginTransaction(Unknown Source)
....
原因是Hibernate正在使用thread
managed会话。使用这种类型的会话管理,Hibernate为您管理会话。当您第一次尝试使用会话时,Hibernate将创建一个会话并将其连接到本地线程。当您在会话中提交事务时,Hibernate将自动关闭会话,这意味着它不能被重用
要解决这个问题,最好的选择是使用managed
会话。使用托管会话,您可以完全控制会话的创建、刷新、提交和关闭。这是怎么做的
在hibernate.cfg.xml
中,将属性current\u session\u context\u class
更改为managed
要在该会话中创建会话
并启动事务
,请执行以下操作
org.hibernate.classic.Session session = HibernateUtil.getSessionFactory().openSession();
session.setFlushMode(FlushMode.MANUAL);
ManagedSessionContext.bind(session);
session.beginTransaction();
ManagedSessionContext.unbind(HibernateUtil.getSessionFactory());
session.flush();
session.getTransaction().commit();
session.close();
要在会话
中提交事务
,请执行以下操作
org.hibernate.classic.Session session = HibernateUtil.getSessionFactory().openSession();
session.setFlushMode(FlushMode.MANUAL);
ManagedSessionContext.bind(session);
session.beginTransaction();
ManagedSessionContext.unbind(HibernateUtil.getSessionFactory());
session.flush();
session.getTransaction().commit();
session.close();
为了在单元测试中使用这段代码,我创建了这个基本单元测试类,所有单元测试都扩展了它。每当我想创建一个新的会话
或事务
时,我调用方法createNewSessionAndTransaction()
。要提交会话的事务,我调用方法commitTransaction()
尝试将此添加到控制器方法:
@Transactional(readOnly = true)
这真的很有帮助,应该是公认的答案。