Managing session-scoped object in a conversation

[vk101]

If you have a session scoped object (e.g. for the currently logged-in User), what do you do within a conversation to get that User object managed under that conversation's EntityManager? The conversation-scoped EntityManager manages objects under a conversation scope but not the session scope.

(Neither EntityManager's refresh() or merge() methods do the trick, throwing exceptions when passed the User object as an argument.)

Thanks.

[gjeudy]

EntityManager.merge() should work, can you give detailed usecase and stacktrace?

[schlegel]

Hi Veer

or you could try to reattach the user entity with

        entityManager.getReference(User.class, , myUser.getId());

[vk101]

Guillaume, EntityManager's merge() gives the following error. The issue seems to be org.hibernate.MappingException: Unknown entity: org.jboss.seam.persistence.EntityManagerProxy

Also, thanks for the suggestion Hans, I'll try it out - I am interested to know why merge() doesn't work, as that seems to be the more common way to do this (never seen getReference used before).

11-Sep-2008 7:16:59 AM com.sun.facelets.FaceletViewHandler handleRenderException
SEVERE: Error Rendering View[/pagetwo.xhtml]
javax.faces.FacesException: javax.el.ELException: /page2.xhtml @49,180 rendered="#{not fileGetter.fileExists}": Error reading 'fileExists' on type internal.test.FileGetter_$$_javassist_4
at javax.faces.component.UIComponentBase.isRendered(UIComponentBase.java:373)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:880)
at javax.faces.render.Renderer.encodeChildren(Renderer.java:137)
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:812)
at org.ajax4jsf.renderkit.RendererBase.renderChild(RendererBase.java:282)
at org.ajax4jsf.renderkit.RendererBase.renderChildren(RendererBase.java:262)
at org.richfaces.renderkit.html.PanelRenderer.doEncodeChildren(PanelRenderer.java:199)
at org.richfaces.renderkit.html.PanelRenderer.doEncodeChildren(PanelRenderer.java:194)
at org.ajax4jsf.renderkit.RendererBase.encodeChildren(RendererBase.java:121)
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:812)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:886)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:892)
at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:592)
at org.ajax4jsf.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:108)
at org.ajax4jsf.application.AjaxViewHandler.renderView(AjaxViewHandler.java:216)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:106)
at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:251)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:144)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:245)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83)
at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:85)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:141)
at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:281)
at org.jboss.seam.web.Ajax4jsfFilter.doFilter(Ajax4jsfFilter.java:60)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.debug.hot.HotDeployFilter.doFilter(HotDeployFilter.java:68)
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)
Caused by: javax.el.ELException: /page2.xhtml @49,180 rendered="#{not fileGetter.fileExists}": Error reading 'fileExists' on type internal.test.FileGetter_$$_javassist_4
at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:76)
at javax.faces.component.UIComponentBase.isRendered(UIComponentBase.java:370)
... 47 more
Caused by: java.lang.IllegalArgumentException: Unknown entity: org.jboss.seam.persistence.EntityManagerProxy
at org.hibernate.ejb.AbstractEntityManagerImpl.merge(AbstractEntityManagerImpl.java:234)
at org.jboss.seam.persistence.EntityManagerProxy.merge(EntityManagerProxy.java:130)
at internal.test.FileGetter.getFileExists(FileGetter.java:30)
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:597)
at org.jboss.seam.util.Reflections.invoke(Reflections.java:21)
at org.jboss.seam.intercept.RootInvocationContext.proceed(RootInvocationContext.java:31)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:56)
at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:46)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.jboss.seam.persistence.ManagedEntityIdentityInterceptor.aroundInvoke(ManagedEntityIdentityInterceptor.java:48)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.jboss.seam.transaction.RollbackInterceptor.aroundInvoke(RollbackInterceptor.java:31)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:42)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107)
at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:166)
at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:102)
at internal.test.MainAction_$$_javassist_4.getFileExists(FileGetter_$$_javassist_4.java)
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:597)
at javax.el.BeanELResolver.getValue(BeanELResolver.java:62)
at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:53)
at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:64)
at org.jboss.el.parser.AstPropertySuffix.getValue(AstPropertySuffix.java:53)
at org.jboss.el.parser.AstValue.getValue(AstValue.java:67)
at org.jboss.el.parser.AstNot.getValue(AstNot.java:26)
at org.jboss.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:71)
... 48 more
Caused by: org.hibernate.MappingException: Unknown entity: org.jboss.seam.persistence.EntityManagerProxy
at org.hibernate.impl.SessionFactoryImpl.getEntityPersister(SessionFactoryImpl.java:550)
at org.hibernate.impl.SessionImpl.getEntityPersister(SessionImpl.java:1338)
at org.hibernate.event.def.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:97)
at org.hibernate.event.def.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:53)
at org.hibernate.impl.SessionImpl.fireMerge(SessionImpl.java:677)
at org.hibernate.impl.SessionImpl.merge(SessionImpl.java:661)
at org.hibernate.impl.SessionImpl.merge(SessionImpl.java:665)
at org.hibernate.ejb.AbstractEntityManagerImpl.merge(AbstractEntityManagerImpl.java:228)
... 81 more

[gjeudy]

By the error message it looks like you are passing a

org.jboss.seam.persistence.EntityManagerProxy

instance to EntityManager.merge()

can you validate?

If thats not the case I suggest you download hibernate source and step through code, hibernate sometimes give misleading error messages and only debugging would give you root cause.