In the samples I have seen the collections were mapped with the attribute lazy="true". I would prefer this option to improve performance however it causes the exception below. If I remove lazy="true" it runs ok.

What should I do to fix this problem?

Thanks.
Jerry.


<set name="transactions" cascade="all" inverse="true" lazy="true">
<key column="tnumber"/>
<one-to-many class="someClass"/>
</set>


11:57:57,980 ERROR LazyInitializationException:25 - Failed to lazily initialize
a collection - no Session
net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a coll
ection - no Session
at net.sf.hibernate.collection.PersistentCollection.initialize(Persisten
tCollection.java:213)
at net.sf.hibernate.collection.PersistentCollection.read(PersistentColle
ction.java:69)
at net.sf.hibernate.collection.Set.size(Set.java:107)
at au.com.countryenergy.legacyarchive.webapp.action.customer.ViewStoresA
ction.execute(ViewStoresAction.java:42)
at org.apache.struts.action.RequestProcessor.processActionPerform(Reques
tProcessor.java:484)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.ja
va:274)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:148
2)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:507)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:743)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Appl
icationFilterChain.java:284)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationF
ilterChain.java:204)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperV
alve.java:256)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValv
eContext.java:151)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.jav
a:564)
at org.apache.catalina.core.StandardContextValve.invokeInternal(Standard
ContextValve.java:245)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextV
alve.java:199)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValv
eContext.java:151)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.jav
a:564)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.j
ava:195)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValv
eContext.java:151)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.j
ava:164)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValv
eContext.java:149)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.jav
a:564)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineVal
ve.java:156)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValv
eContext.java:151)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.jav
a:564)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:972)

at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:21
1)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java
:805)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.proce
ssConnection(Http11Protocol.java:696)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java
:605)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadP
ool.java:677)
at java.lang.Thread.run(Thread.java:534)
11:57:58,027 WARN RequestProcessor:538 - Unhandled Exception thrown: class net.
sf.hibernate.LazyInitializationException

Well, as you haven't posted any of the code driving the interaction which generates this error I guess we'll have to guess.

Most definitely you are closing the session prior to accessing the collection. How exactly that happens is in the details you left out of your post...