我正在使用hibernate 3.6.7进行从类到oracle表的映射。
我通常不会收到此异常:
org.hibernate.HibernateException: Unable to access lob stream
at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222)
at java.util.concurrent.FutureTask.get(FutureTask.java:83)
at com.mycompany.TransferFiles.TransferFilesToHadoop(TransferFiles.java:85)
at com.mycompany.TransferJob.execute(TransferJob.java:25)
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:525)
Caused by: org.hibernate.HibernateException: Unable to access lob stream
at org.hibernate.type.descriptor.java.ClobTypeDescriptor.unwrap(ClobTypeDescriptor.java:117)
at org.hibernate.type.descriptor.java.ClobTypeDescriptor.unwrap(ClobTypeDescriptor.java:46)
at org.hibernate.type.descriptor.sql.ClobTypeDescriptor$3$1.doBind(ClobTypeDescriptor.java:83)
at org.hibernate.type.descriptor.sql.BasicBinder.bind(BasicBinder.java:91)
at org.hibernate.type.AbstractStandardBasicType.nullSafeSet(AbstractStandardBasicType.java:283)
at org.hibernate.type.AbstractStandardBasicType.nullSafeSet(AbstractStandardBasicType.java:278)
at org.hibernate.type.AbstractSingleColumnStandardBasicType.nullSafeSet(AbstractSingleColumnStandardBasicType.java:89)
at org.hibernate.persister.entity.AbstractEntityPersister.dehydrate(AbstractEntityPersister.java:2184)
at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:2558)
at org.hibernate.persister.entity.AbstractEntityPersister.updateOrInsert(AbstractEntityPersister.java:2494)
at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:2821)
at org.hibernate.action.EntityUpdateAction.execute(EntityUpdateAction.java:113)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:265)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:185)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:51)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216)
at com.mycompany.HibernateUtil.getSession(HibernateUtil.java:36)
at com.mycompany.BasicDaoImpl.saveOrUpdate(BasicDaoImpl.java:34)
at com.mycompany.FileCopyRoutine.call(TransferFiles.java:297)
at com.mycompany..FileCopyRoutine.call(TransferFiles.java:225)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.sql.SQLException: Closed Connection
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:146)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:208)
at oracle.sql.CLOB.getDBAccess(CLOB.java:1196)
at oracle.sql.CLOB.getCharacterStream(CLOB.java:278)
at sun.reflect.GeneratedMethodAccessor29.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.hibernate.engine.jdbc.SerializableClobProxy.invoke(SerializableClobProxy.java:74)
at $Proxy2.getCharacterStream(Unknown Source)
at org.hibernate.type.descriptor.java.ClobTypeDescriptor.unwrap(ClobTypeDescriptor.java:114)
当我调用saveOrUpdate方法时。
有人可以给我一些建议吗？
public static synchronized Session getSession() throws DBConnectionException{
Session session = threadSession.get();
if(session==null||!session.isOpen()||!session.isConnected()){
if(sessionFactory==null||sessionFactory.isClosed())initHibernate();
try{
session = sessionFactory.openSession();
}catch(Exception e){
throw new DBConnectionException("Exception caught when trying to generate Hibernate session.");
}
threadSession.set(session);
}
if(session.isDirty()){
session.flush();(36 line of HibernateUtil)
}
session.clear();
return session;
}
我使用了很长时间。
现在我要并行传输文件，然后使用saveOrUpdate方法更新数据库。由于线程很多，我在代码中同步了这一部分。
我认为我们一直都有与数据库的连接，但是它提供了封闭连接的排他性。
任何人都可以给我一些有关此异常的建议。问题应该是什么？
我以为是因为使用了saveOrUpdate，所以我更改为合并，但是相同的问题也相同。
Caused by: org.hibernate.HibernateException: Unable to access lob stream
at org.hibernate.type.descriptor.java.ClobTypeDescriptor.unwrap(ClobTypeDescriptor.java:117)
at org.hibernate.type.descriptor.java.ClobTypeDescriptor.unwrap(ClobTypeDescriptor.java:46)
at org.hibernate.type.descriptor.sql.ClobTypeDescriptor$3$1.doBind(ClobTypeDescriptor.java:83)
at org.hibernate.type.descriptor.sql.BasicBinder.bind(BasicBinder.java:91)
at org.hibernate.type.AbstractStandardBasicType.nullSafeSet(AbstractStandardBasicType.java:283)
at org.hibernate.type.AbstractStandardBasicType.nullSafeSet(AbstractStandardBasicType.java:278)
at org.hibernate.type.AbstractSingleColumnStandardBasicType.nullSafeSet(AbstractSingleColumnStandardBasicType.java:89)
at org.hibernate.persister.entity.AbstractEntityPersister.dehydrate(AbstractEntityPersister.java:2184)
at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:2558)
at org.hibernate.persister.entity.AbstractEntityPersister.updateOrInsert(AbstractEntityPersister.java:2494)
at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:2821)
at org.hibernate.action.EntityUpdateAction.execute(EntityUpdateAction.java:113)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:265)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:185)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:51)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:383)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:133)
at mycompany.jobsrc.BasicDaoImpl.merge(BasicDaoImpl.java:52)
at mycompany.FileCopyRoutine.call(TransferFiles.java:301)
at mycompany.FileCopyRoutine.call(TransferFiles.java:226)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.sql.SQLException: Closed Connection
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:146)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:208)
at oracle.sql.CLOB.getDBAccess(CLOB.java:1196)
at oracle.sql.CLOB.getCharacterStream(CLOB.java:278)
at sun.reflect.GeneratedMethodAccessor36.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.hibernate.engine.jdbc.SerializableClobProxy.invoke(SerializableClobProxy.java:74)
at $Proxy2.getCharacterStream(Unknown Source)
at org.hibernate.type.descriptor.java.ClobTypeDescriptor.unwrap(ClobTypeDescriptor.java:114)
... 27 more
我的合并代码:
public void merge(T t) throws DBConnectionException{
Session session = HibernateUtil.getSession();
Transaction transaction = session.beginTransaction();
session.merge(t);
transaction.commit();
}
最佳答案
尝试在尝试访问lob字段对象的服务方法上添加 @Transactional 。
它为我工作。