outer-joins with hibernate

[marco4712]

hi,

i am using spring together with hibernate. all works fine, but i am stuck with the following problem:

if i have one-to-one or many-to-one relations, i want to use outer-joins instead of firing a lot of select statements. therefore i declared my classes as proxies for themselves with <class name="..." ... lazy="true">.
but this doesnt work for me, because of using spring i always get an exception, that the session is already closed.

i would really appreciate any help.

thanks in advance
marco

[robh]

Marco,

Check out the JavaDocs for OpenSessionInViewFilter and OpenSessionInViewInterceptor with which you can bind a Session to the thread for a particular request. Spring will then keep this Session alive for the request allowing for lazy loading to work in the web tier.

Rob

[marco4712]

thanks robh for your help. i applied the opensessioninviewinterceptor, but the exception still remained. i tried it with the servletwrappingcontroller, because i am using hibernate, spring and struts together. below i attach the relevant parts of my applicationContext-hibernate.xml.

<bean id="transactionManager_"
class="org.springframework.orm.hibernate.Hibernate TransactionManager">
<property name="sessionFactory">
<ref local="sessionFactory_"/>
</property>
</bean>
<bean id="persistenceService"
class="org.springframework.aop.framework.ProxyFact oryBean">
<property name="proxyInterfaces">
<value>abs.proto2.db.IPersistenceService</value>
</property>
<property name="interceptorNames">
<value>transactionInterceptor_,persistenceTarget </value>
</property>
</bean>
<bean id="transactionInterceptor_"
class="org.springframework.transaction.interceptor .TransactionInterceptor">
<property name="transactionManager">
<ref local="transactionManager_"/>
</property>
<property name="transactionAttributeSource">
<value>abs.proto2.db.IPersistenceService.*=PROPAGA TION_REQUIRED</value>
</property>
</bean>
<bean id="urlMapping" class="org.springframework.web.servlet.handler.Sim pleUrlHandlerMapping">
<property name="interceptors">
<list>
<ref bean="openSessionInViewInterceptor"/>
</list>
</property>
<property name="mappings">
<props>
<prop key="*.do">strutsWrappingController</prop>
</props>
</property>
</bean>

<bean id="strutsWrappingController" class="org.springframework.web.servlet.mvc.Servlet WrappingController">
<property name="servletClass">
<value>org.apache.struts.action.ActionServlet</value>
</property>
<property name="servletName">
<value>action</value>
</property>
<property name="initParameters">
<props>
<prop key="config">/WEB-INF/struts-config.xml</prop>
</props>
</property>
</bean>
<bean name="openSessionInViewInterceptor"
class="org.springframework.orm.hibernate.support.O penSessionInViewInterceptor">
<property name="sessionFactory">
<ref local="sessionFactory_"/>
</property>
</bean>


[ERROR] 2005-01-11 17:25:25,363 net.sf.hibernate.proxy.LazyInitializer - Line: 63 Exception initializing proxy
net.sf.hibernate.HibernateException: Could not initialize proxy - the owning Session was closed
at net.sf.hibernate.proxy.LazyInitializer.initialize( LazyInitializer.java:47)
at net.sf.hibernate.proxy.LazyInitializer.initializeW rapExceptions(LazyInitializer.java:60)
at net.sf.hibernate.proxy.LazyInitializer.getImplemen tation(LazyInitializer.java:164)
at net.sf.hibernate.proxy.CGLIBLazyInitializer.interc ept(CGLIBLazyInitializer.java:108)
at abs.proto2.beans.Eingabe$$EnhancerByCGLIB$$b02bc83 4.getStatus(<generated>)
at abs.proto2.actions.FormSbAction.execute(FormSbActi on.java:104)
at org.apache.struts.action.RequestProcessor.processA ctionPerform(RequestProcessor.java:421)
at org.apache.struts.action.RequestProcessor.process( RequestProcessor.java:226)
at org.apache.struts.action.ActionServlet.process(Act ionServlet.java:1164)
at org.apache.struts.action.ActionServlet.doGet(Actio nServlet.java:397)
at javax.servlet.http.HttpServlet.service(HttpServlet .java:689)
at javax.servlet.http.HttpServlet.service(HttpServlet .java:802)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:237)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:157)
at org.apache.catalina.core.StandardWrapperValve.invo ke(StandardWrapperValve.java:214)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.StandardContextValve.invo keInternal(StandardContextValve.java:198)
at org.apache.catalina.core.StandardContextValve.invo ke(StandardContextValve.java:152)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.StandardHostValve.invoke( StandardHostValve.java:137)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.valves.ErrorReportValve.invoke (ErrorReportValve.java:117)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:102)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.StandardEngineValve.invok e(StandardEngineValve.java:109)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.ContainerBase.invoke(Cont ainerBase.java:929)
at org.apache.coyote.tomcat5.CoyoteAdapter.service(Co yoteAdapter.java:160)
at org.apache.coyote.http11.Http11Processor.process(H ttp11Processor.java:799)
at org.apache.coyote.http11.Http11Protocol$Http11Conn ectionHandler.processConnection(Http11Protocol.jav a:705)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(P oolTcpEndpoint.java:577)
at org.apache.tomcat.util.threads.ThreadPool$ControlR unnable.run(ThreadPool.java:683)
at java.lang.Thread.run(Thread.java:534)
[FATAL] 2005-01-11 17:25:25,394 org.apache.struts.action.ExceptionHandler - Line: 31 Exception wurde verursacht:
net.sf.hibernate.LazyInitializationException: Exception initializing proxy: [abs.proto2.beans.Eingabe#16016]
at net.sf.hibernate.proxy.LazyInitializer.initializeW rapExceptions(LazyInitializer.java:64)
at net.sf.hibernate.proxy.LazyInitializer.getImplemen tation(LazyInitializer.java:164)
at net.sf.hibernate.proxy.CGLIBLazyInitializer.interc ept(CGLIBLazyInitializer.java:108)
at abs.proto2.beans.Eingabe$$EnhancerByCGLIB$$b02bc83 4.getStatus(<generated>)
at abs.proto2.actions.FormSbAction.execute(FormSbActi on.java:104)
at org.apache.struts.action.RequestProcessor.processA ctionPerform(RequestProcessor.java:421)
at org.apache.struts.action.RequestProcessor.process( RequestProcessor.java:226)
at org.apache.struts.action.ActionServlet.process(Act ionServlet.java:1164)
at org.apache.struts.action.ActionServlet.doGet(Actio nServlet.java:397)
at javax.servlet.http.HttpServlet.service(HttpServlet .java:689)
at javax.servlet.http.HttpServlet.service(HttpServlet .java:802)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:237)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:157)
at org.apache.catalina.core.StandardWrapperValve.invo ke(StandardWrapperValve.java:214)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.StandardContextValve.invo keInternal(StandardContextValve.java:198)
at org.apache.catalina.core.StandardContextValve.invo ke(StandardContextValve.java:152)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.StandardHostValve.invoke( StandardHostValve.java:137)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.valves.ErrorReportValve.invoke (ErrorReportValve.java:117)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:102)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.StandardEngineValve.invok e(StandardEngineValve.java:109)
at org.apache.catalina.core.StandardValveContext.invo keNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(S tandardPipeline.java:520)
at org.apache.catalina.core.ContainerBase.invoke(Cont ainerBase.java:929)
at org.apache.coyote.tomcat5.CoyoteAdapter.service(Co yoteAdapter.java:160)
at org.apache.coyote.http11.Http11Processor.process(H ttp11Processor.java:799)
at org.apache.coyote.http11.Http11Protocol$Http11Conn ectionHandler.processConnection(Http11Protocol.jav a:705)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(P oolTcpEndpoint.java:577)
at org.apache.tomcat.util.threads.ThreadPool$ControlR unnable.run(ThreadPool.java:683)
at java.lang.Thread.run(Thread.java:534)
Caused by: net.sf.hibernate.HibernateException: Could not initialize proxy - the owning Session was closed
at net.sf.hibernate.proxy.LazyInitializer.initialize( LazyInitializer.java:47)
at net.sf.hibernate.proxy.LazyInitializer.initializeW rapExceptions(LazyInitializer.java:60)
... 34 more