Hi,

I am a newbie in Hibernate and I have the following situation:

I use Hiberante 2.1.7 integrated with JBoss 3.2.3 and we have the problem that, by default, Hibernate loads the objects with all the assosiated objects and that means that for every simple query that is made Hibernate constructs the hole Object with information that, for most cases, it is not necesary. So we tried to use the lazy="true" (in the mapping files) in that way Hibernate retrieves the object "on-demand", but we had problems here is what happend:

The problem is that our business layer uses Session Beans for scalability. This way when a service is required it is provided by the Session Bean which eventually use Hibernate to retrieve the information from a database. When lazy where equal to false, there were no problem because a Session Bean method encapsulate a transaction and Hibernate query ran inside that transaction. The problem appears when lazy="true" because, at the end of the execution of the business method of the Session bean the application server, JBoss 3.2.3, fails and throws the following log:

2006-01-26 14:56:15,750 INFO [org.jboss.resource.connectionmanager.CachedConnectionManager] Closing a connection for you. Please close them yourself: org.jboss.resource.adapter.jdbc.WrappedConnection@1116790
java.lang.Exception: STACKTRACE
at org.jboss.resource.connectionmanager.CachedConnectionManager.registerConnection(CachedConnectionManager.java:282)
at org.jboss.resource.connectionmanager.BaseConnectionManager2.allocateConnection(BaseConnectionManager2.java:506)
at org.jboss.resource.connectionmanager.BaseConnectionManager2$ConnectionManagerProxy.allocateConnection(BaseConnectionManager2.java:814)
at org.jboss.resource.adapter.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:102)
at net.sf.hibernate.connection.DatasourceConnectionProvider.getConnection(DatasourceConnectionProvider.java:59)
at net.sf.hibernate.impl.BatcherImpl.openConnection(BatcherImpl.java:289)
at net.sf.hibernate.impl.SessionImpl.connect(SessionImpl.java:3361)
at net.sf.hibernate.impl.SessionImpl.connection(SessionImpl.java:3321)
at net.sf.hibernate.impl.BatcherImpl.prepareQueryStatement(BatcherImpl.java:66)
at net.sf.hibernate.loader.Loader.prepareQueryStatement(Loader.java:779)
at net.sf.hibernate.loader.Loader.doQuery(Loader.java:265)
at net.sf.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:133)
at net.sf.hibernate.loader.Loader.doList(Loader.java:1033)
at net.sf.hibernate.loader.Loader.list(Loader.java:1024)
at net.sf.hibernate.hql.QueryTranslator.list(QueryTranslator.java:854)
at net.sf.hibernate.impl.SessionImpl.find(SessionImpl.java:1553)
at net.sf.hibernate.impl.QueryImpl.list(QueryImpl.java:39)
at net.sf.hibernate.impl.AbstractQueryImpl.uniqueResult(AbstractQueryImpl.java:550)
at uy.com.isbel.crmop.incidents.core.IncidentServicesImpl.getIncidentStatusByCode(IncidentServicesImpl.java:2155)
at uy.com.isbel.crmop.incidents.ejb.IncidentServicesBean.getIncidentStatusByCode(IncidentServicesBean.java:517)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.jboss.ejb.StatelessSessionContainer$ContainerInterceptor.invoke(StatelessSessionContainer.java:683)
at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.invoke(CachedConnectionInterceptor.java:185)
at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:84)
at org.jboss.ejb.plugins.AbstractTxInterceptorBMT.invokeNext(AbstractTxInterceptorBMT.java:144)
at org.jboss.ejb.plugins.TxInterceptorBMT.invoke(TxInterceptorBMT.java:62)
at org.jboss.ejb.plugins.StatelessSessionInstanceInterceptor.invoke(StatelessSessionInstanceInterceptor.java:72)
at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:118)
at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:191)
at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:122)
at org.jboss.ejb.StatelessSessionContainer.internalInvoke(StatelessSessionContainer.java:331)
at org.jboss.ejb.Container.invoke(Container.java:700)
at org.jboss.ejb.plugins.local.BaseLocalProxyFactory.invoke(BaseLocalProxyFactory.java:375)
at org.jboss.ejb.plugins.local.StatelessSessionProxy.invoke(StatelessSessionProxy.java:83)
at $Proxy66.getIncidentStatusByCode(Unknown Source)
at uy.com.isbel.crmop.incidents.services.IncidentServicesBusinessDelegate.getIncidentStatusByCode(IncidentServicesBusinessDelegate.java:526)
at uy.com.isbel.crmop.presentation.controller.PruebaFilter.something(PruebaFilter.java:52)
at uy.com.isbel.crmop.presentation.controller.PruebaFilter.pageRequested(PruebaFilter.java:78)
at com.salmonllc.html.HtmlPage.notifyListeners(HtmlPage.java:1169)
at com.salmonllc.jsp.JspController.notifyListeners(JspController.java:1219)
at com.salmonllc.jsp.JspController.doGet(JspController.java:701)
at com.salmonllc.jsp.tags.PageTag.doStartTag(PageTag.java:224)
at org.apache.jsp.pruebaFilter_jsp._jspx_meth_salmon_page_0(pruebaFilter_jsp.java:147)
at org.apache.jsp.pruebaFilter_jsp._jspService(pruebaFilter_jsp.java:109)
at com.salmonllc.jsp.JspServlet.service(JspServlet.java:332)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:210)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at uy.com.isbel.web.filter.HibernateThreadFilter.doFilter(HibernateThreadFilter.java:41)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.jboss.web.tomcat.security.JBossSecurityMgrRealm.invoke(JBossSecurityMgrRealm.java:220)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.jboss.web.tomcat.tc4.statistics.ContainerStatsValve.invoke(ContainerStatsValve.java:76)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2417)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:65)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:577)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:197)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:781)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:549)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:605)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:677)
at java.lang.Thread.run(Thread.java:534)
2006-01-26 14:56:15,765 INFO [STDOUT] parece joda3772
2006-01-26 14:56:15,765 INFO [STDOUT] Hibernate: select user0_.IdUsuario as IdUsuario1_, user0_.Nombre as Nombre1_, user0_.Email as Email1_, user0_.DESCRIPCION as DESCRIPC4_1_, user0_.BORRADO as BORRADO1_, user0_.IDCANAL as IDCANAL1_, channel1_.ID as ID0_, channel1_.CODIGO as CODIGO0_, channel1_.DESCRIPCION as DESCRIPC3_0_, channel1_.HABILITADO as HABILITADO0_ from Usuarios user0_, CANALES channel1_ where user0_.IdUsuario=? and user0_.IDCANAL=channel1_.ID(+)
2006-01-26 14:56:15,765 WARN [net.sf.hibernate.util.JDBCExceptionReporter] SQL Error: 0, SQLState: null
2006-01-26 14:56:15,765 ERROR [net.sf.hibernate.util.JDBCExceptionReporter] Connection handle has been closed and is unusable
2006-01-26 14:56:15,781 WARN [net.sf.hibernate.util.JDBCExceptionReporter] SQL Error: 0, SQLState: null
2006-01-26 14:56:15,781 ERROR [net.sf.hibernate.util.JDBCExceptionReporter] Connection handle has been closed and is unusable
2006-01-26 14:56:15,781 ERROR [net.sf.hibernate.proxy.LazyInitializer] Exception initializing proxy
net.sf.hibernate.exception.GenericJDBCException: could not load: [uy.com.isbel.crmop.security.vo.User#426]
at net.sf.hibernate.exception.ErrorCodeConverter.handledNonSpecificException(ErrorCodeConverter.java:90)
at net.sf.hibernate.exception.ErrorCodeConverter.convert(ErrorCodeConverter.java:79)
at net.sf.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:30)
at net.sf.hibernate.persister.AbstractEntityPersister.convert(AbstractEntityPersister.java:1332)
at net.sf.hibernate.persister.EntityPersister.load(EntityPersister.java:418)
at net.sf.hibernate.impl.SessionImpl.doLoad(SessionImpl.java:2130)
at net.sf.hibernate.impl.SessionImpl.immediateLoad(SessionImpl.java:1944)
at net.sf.hibernate.proxy.LazyInitializer.initialize(LazyInitializer.java:53)
at net.sf.hibernate.proxy.LazyInitializer.initializeWrapExceptions(LazyInitializer.java:60)
at net.sf.hibernate.proxy.LazyInitializer.getImplementation(LazyInitializer.java:164)
at net.sf.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:108)
at uy.com.isbel.crmop.security.vo.User$$EnhancerByCGLIB$$8bb5a917.getName(<generated>)
at uy.com.isbel.crmop.presentation.controller.PruebaFilter.something(PruebaFilter.java:73)
at uy.com.isbel.crmop.presentation.controller.PruebaFilter.pageRequested(PruebaFilter.java:78)
at com.salmonllc.html.HtmlPage.notifyListeners(HtmlPage.java:1169)
at com.salmonllc.jsp.JspController.notifyListeners(JspController.java:1219)
at com.salmonllc.jsp.JspController.doGet(JspController.java:701)
at com.salmonllc.jsp.tags.PageTag.doStartTag(PageTag.java:224)
at org.apache.jsp.pruebaFilter_jsp._jspx_meth_salmon_page_0(pruebaFilter_jsp.java:147)
at org.apache.jsp.pruebaFilter_jsp._jspService(pruebaFilter_jsp.java:109)
at com.salmonllc.jsp.JspServlet.service(JspServlet.java:332)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:210)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at uy.com.isbel.web.filter.HibernateThreadFilter.doFilter(HibernateThreadFilter.java:41)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.jboss.web.tomcat.security.JBossSecurityMgrRealm.invoke(JBossSecurityMgrRealm.java:220)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.jboss.web.tomcat.tc4.statistics.ContainerStatsValve.invoke(ContainerStatsValve.java:76)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2417)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:65)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:577)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:197)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:781)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:549)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:605)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:677)
at java.lang.Thread.run(Thread.java:534)
Caused by: java.sql.SQLException: Connection handle has been closed and is unusable
at org.jboss.resource.adapter.jdbc.WrappedConnection.checkStatus(WrappedConnection.java:774)
at org.jboss.resource.adapter.jdbc.WrappedConnection.checkTransaction(WrappedConnection.java:759)
at org.jboss.resource.adapter.jdbc.WrappedConnection.prepareStatement(WrappedConnection.java:208)
at net.sf.hibernate.impl.BatcherImpl.getPreparedStatement(BatcherImpl.java:260)
at net.sf.hibernate.impl.BatcherImpl.getPreparedStatement(BatcherImpl.java:235)
at net.sf.hibernate.impl.BatcherImpl.prepareQueryStatement(BatcherImpl.java:66)
at net.sf.hibernate.loader.Loader.prepareQueryStatement(Loader.java:779)
at net.sf.hibernate.loader.Loader.doQuery(Loader.java:265)
at net.sf.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:133)
at net.sf.hibernate.loader.Loader.loadEntity(Loader.java:911)
at net.sf.hibernate.loader.Loader.loadEntity(Loader.java:931)
at net.sf.hibernate.loader.EntityLoader.load(EntityLoader.java:59)
at net.sf.hibernate.loader.EntityLoader.load(EntityLoader.java:51)
at net.sf.hibernate.persister.EntityPersister.load(EntityPersister.java:415)
... 62 more

Another important thing to mention is when I use the exact same code that is defined inside the Session Bean method (which uses Hibernate) works just fine if i use it outside the Sesssion Bean method, for example if I use it in the presentation layer directly I just works with lazy="true"

Any suggestion would help me,

Thanks a lot.
Marcelo.

I would suggest limiting use of “lazy” feature and refactoring SessionBean interface that it will return list of information about objects – not the objects themselves ( retrieved as named SQL with complex joins perhaps ) and then separate method will return fully initialized objects on demand or will operate on user specified object.

Thank you, for the answer. I think that the solution probably is what you suggest.

But...;). Before I start implementing that solution, I would like to know if there is a way that you can tell JBoss, or an J2EE application server in general, to don't close any JTA transaction at the end of a stateless session bean method. I think that it is the problem that is happening here. If there is no way to do that, then I have no choise but refactor all session bean methods, which are a lot.. :(.

Thank you again,
Marcelo

I suppose this is possible if you will take trouble to specify bean managed transaction type in the SB descriptor and will manage transactions yourself.

And/or declare appropriate transaction attributes on methods so only entry method will start transaction and others will participate in the transaction if called in the course of this invocation.

Stateful session beans with client demarcated transactions can help, but if you need remote initialization then you will need some custom stuff for hibernate. It is incomplete implementation, but I hope this idea can help http://www.hibernate.org/377.html

The proper way is to make sure that the SessionBean has loaded all the data the client will require *before* serializing it back to the client.