I run this query:

results = session.createQuery("SELECT p FROM ContactSheetPerson csp, Person p WHERE csp.id.personid = p.personid AND csp.id.contactsheetid=" + sheetId).list();

Where ContactSheetPerson is a bridge between person and contactSheet tables.

Everything works okay with the query it seems but when I attempt to dump the data in my jsp I get an error if any of the columns are blank (nulls are allowed everywhere but id and name). Its a mySql db. Here's the full exception:

java.lang.ClassCastException
at org.hibernate.type.StringType.toString(StringType.java:42)
at org.hibernate.type.NullableType.toLoggableString(NullableType.java:122)
at org.hibernate.type.CollectionType.toLoggableString(CollectionType.java:147)
at org.hibernate.pretty.Printer.toString(Printer.java:53)
at org.hibernate.pretty.Printer.toString(Printer.java:90)
at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(Abstrac
tFlushingEventListener.java:91)
at org.hibernate.event.def.DefaultAutoFlushEventListener.onAutoFlush(DefaultAutoFlushEventLi
stener.java:39)
at org.hibernate.impl.SessionImpl.autoFlushIfRequired(SessionImpl.java:711)
at org.hibernate.impl.SessionImpl.prepareQueries(SessionImpl.java:895)
at org.hibernate.impl.SessionImpl.getQueries(SessionImpl.java:885)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:834)
at org.hibernate.impl.QueryImpl.list(QueryImpl.java:74)
at com.eaton.ee.teamcontacts3.dao.ContactSheetDAO.getSheetsByTeam(ContactSheetDAO.java:168)
at com.eaton.ee.teamcontacts3.dao.teamDAO.getTeamById(teamDAO.java:46)
at com.eaton.ee.teamcontacts3.action.ViewTeam.execute(ViewTeam.java:54)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:484)

at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:274)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:507)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.j
ava:247)
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$StandardPipelineValveContext.invokeNext(Standar
dPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(Standar
dPipeline.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.StandardContext.invoke(StandardContext.java:2417)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(Standar
dPipeline.java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(Standar
dPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(Standar
dPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(Standar
dPipeline.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:193)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:781)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11P
rotocol.java:549)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:589)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:666)
at java.lang.Thread.run(Thread.java:536)
Hibernate: select team0_.teamId as teamId0_, team0_.name as name1_0_, team0_.description as descript
3_1_0_ from team team0_ where team0_.teamId=?


I tested by entering items in all the rows and sure enough it will output fine then. Just has problems when a field is left blank. Any suggestions? Thanks!

Do you have log4j for Hibernate set to DEBUG mode? I'm getting a similar error when I run in DEBUG mode, but if you set it to WARN then I don't get the error.

If you have it in DEBUG, try to see if the error still occurs when it's set to WARN. This may be a Hibernate bug.

Actually log4j isn't set up on this project. Its kinda a small test project to see if we want to use hibernate for an upcoming project. I've been meaning to get log4j up. Maybe i'll do that today. I'll post again if anything changes once logging is in place. Thanks.

I also was getting an error due to the loglevel being set to debug. I thought, bug!, but waited. I didn't actually try changing the log level. In my case, this was the first time I had to load a persistent class with a single-column ID. I am mapping legacy data and most of it has composite keys. The other simple-ID persistent classes are associations I never have to look up. All along I had either been using the persistent class itself or a key class to do lookups. Instead the MessageHelper.infoString() call in org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad() was instructive in showing me that Hibernate was expecting a String ID (the type of my single ID column) rather than an ID of the persistent class itself. I modified my call to Session.load() to use a String ID and everything works. I assume this is as-intended behavior.

HTH,
Matt

Hi

results = session.createQuery("SELECT p FROM ContactSheetPerson csp, Person p WHERE csp.id.personid = p.personid AND csp.id.contactsheetid=" + sheetId).list();


Where exactly you can get an error?

1) in the List results?

2) while casting to an Object?

I think session.createQuery will give you a Object Array. If you cast it to an Object in the JSP you will get an ClassCastException.

Well, I wish turning off the debugger worked for me, but unfortunately it had no effect (I still get the same error). Like Matt, I also work with a legacy database, and it not only lacks surrogate keys and profusely uses composite keys, but also has no foreign key constraints. I am not really surprised to have problems mapping sorted collections correctly under the circumstances, but what drives me insane is that these errors are so difficult to trace. I have a good feeling about where the culprit code sits, but the problem does not manifest itself until the next flush. Even surrounding the suspect code with flush statements does not narrow it down enough to know what exactly causes the class cast exception.

I am getting the same error when trying to load a table with nullable string columns...I get this when I go to access the String in a getter:

I'm getting the same error, has this been resolved yet?

It was suggested to change the log level for hibernate, could you instruct me which file I need to change. I am using JBOSS.

Thanks a lot.