[
Date Prev][
Date Next][
Thread Prev][
Thread Next][
Date Index][
Thread Index]
[
List Home]
|
Re: [eclipselink-users] EntityManager.find returning instance of wrong type
|
How would JPA know what row coincides with what subclass? To tell it
that you'll need to use the @DiscriminatorColumn on the parent class
and supply a unique value for each subclass using the
@DiscriminatorValue for the subclasses.
Also, the @Inheritance(strategy=InheritanceType.SINGLE_TABLE)
annotation goes on the parent class.
Zarar
On Fri, Mar 6, 2009 at 8:52 AM, jsw <marvin.438@xxxxxxxxx> wrote:
>
> In my REST service:
>
> public void doTest() {
> long id = 12; // valid id of Bar entity
>
> List<Base> bases = this.facade.getDAO().findAllBase();
>
> Base base = null;
> try {
> if ((base = this.facade.getWorkOrderDAO().findFooById(id)) !=
> null) { // this row will throw an exception
> log.debug("Found Foo");
> } else if ((base =
> this.facade.getWorkOrderDAO().findBarById(id)) != null) {
> log.debug("Found Bar");
> }
>
> } catch (Exception ex) {
> ex.printStackTrace();
> }
> }
>
> And in the DAO class:
>
> @Transactional(readOnly = true, propagation=Propagation.SUPPORTS)
> public List<Base> findAllBase() {
> return em.createQuery("select b from Base b").getResultList();
> }
>
> @Transactional(readOnly = true, propagation=Propagation.SUPPORTS)
> public Foo findFooById(long id) {
> return em.find(Foo.class, id);
> }
>
> @Transactional(readOnly = true, propagation=Propagation.SUPPORTS)
> public Bar findBarById(long id) {
> return em.find(Bar.class, id);
> }
>
> java.lang.ClassCastException: com.acme.planning.dataaccess.model.Bar cannot
> be cast to com.acme.planning.dataaccess.model.Foo
> at com.acme.planning.dataaccess.DAO.findFooById(DAO.java:348)
> at
> com.acme.planning.dataaccess.DAO$$FastClassByCGLIB$$80c0e135.invoke(<generated>)
> at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:191)
> at
> org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:700)
> at
> org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
> at
> org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106)
> at
> org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
> at
> org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:635)
> at
> com.acme.planning.dataaccess.DAO$$EnhancerByCGLIB$$93a24725.findFooById(<generated>)
> at
> com.acme.planning.interaction.rest.MobilogService.test(MobilogService.java:829)
> 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
> com.sun.jersey.server.impl.model.method.dispatch.EntityParamDispatchProvider$ResponseOutInvoker._dispatch(EntityParamDispatchProvider.java:157)
> at
> com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:67)
> at
> com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:154)
> at
> com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:111)
> at
> com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:71)
> at
> com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:111)
> at
> com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:63)
> at
> com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:543)
> at
> com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:502)
> at
> com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:493)
> at
> com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:308)
> at
> com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:314)
> at
> com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:239)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
> at
> com.acme.common.filter.CacheControlFilter.doFilter(CacheControlFilter.java:72)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:378)
> at
> org.springframework.security.intercept.web.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
> at
> org.springframework.security.intercept.web.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.ui.SessionFixationProtectionFilter.doFilterHttp(SessionFixationProtectionFilter.java:67)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.ui.ExceptionTranslationFilter.doFilterHttp(ExceptionTranslationFilter.java:101)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.providers.anonymous.AnonymousProcessingFilter.doFilterHttp(AnonymousProcessingFilter.java:105)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.wrapper.SecurityContextHolderAwareRequestFilter.doFilterHttp(SecurityContextHolderAwareRequestFilter.java:91)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.ui.basicauth.BasicProcessingFilter.doFilterHttp(BasicProcessingFilter.java:174)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.ui.AbstractProcessingFilter.doFilterHttp(AbstractProcessingFilter.java:277)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.ui.logout.LogoutFilter.doFilterHttp(LogoutFilter.java:89)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.context.HttpSessionContextIntegrationFilter.doFilterHttp(HttpSessionContextIntegrationFilter.java:235)
> at
> org.springframework.security.ui.SpringSecurityFilter.doFilter(SpringSecurityFilter.java:53)
> at
> org.springframework.security.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:390)
> at
> org.springframework.security.util.FilterChainProxy.doFilter(FilterChainProxy.java:175)
> at
> org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:236)
> at
> org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
> at
> org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)
> at
> org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
> at
> org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
> 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:230)
> at
> org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
> at
> org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179)
> at
> org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
> at
> org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
> at
> org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
> at
> org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
> at
> org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
> at
> org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:262)
> at
> org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
> at
> org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
> at
> org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:446)
> at java.lang.Thread.run(Thread.java:619)
>
>
> tch wrote:
>>
>> Doesn't sound right, can you post the whole stack trace?
>>
>> ./tch
>>
>>
>>
>> On Fri, Mar 6, 2009 at 7:56 AM, jsw <marvin.438@xxxxxxxxx> wrote:
>>>
>>> OK, thank you, it seems I had misunderstood how to use the @Inheritance
>>> annotation. However, in this case it does not seem to make a difference
>>> since SINGLE_TABLE is the default inheritance type.
>>>
>>> Unfortunately, moving the @Inherintance annotation to the base class did
>>> not
>>> solve my problem. EntityManager.find keeps trying to return an instance
>>> of
>>> the wrong entity.
>>>
>>> Maybe something more I've misunderstood?
>>>
>>>
>>>
>>> tch wrote:
>>>>
>>>> I've never used the @Inheritance annotation, but I believe it goes on
>>>> the base class, not the extending entity.
>>>>
>>>> See:
>>>> http://www.oracle.com/technology/products/ias/toplink/jpa/howto/use-inheritance.html
>>>>
>>>>
>>>>
>>>> On Fri, Mar 6, 2009 at 3:00 AM, jsw <marvin.438@xxxxxxxxx> wrote:
>>>>>
>>>>> Environment: JBoss, Jersey, Spring, EclipseLink JPA, PostgreSQL
>>>>>
>>>>> @Entity
>>>>> public abstract class Base {
>>>>> @Id
>>>>> @GeneratedValue(strategy = GenerationType.TABLE)
>>>>> private Long id;
>>>>>
>>>>> @Version
>>>>> private long version;
>>>>>
>>>>> ...
>>>>> }
>>>>>
>>>>> @Entity
>>>>> @Inheritance(strategy=InheritanceType.SINGLE_TABLE)
>>>>> public class Foo extends Base { ... }
>>>>>
>>>>> @Entity
>>>>> @Inheritance(strategy=InheritanceType.SINGLE_TABLE)
>>>>> public class Bar extends Base { ... }
>>>>>
>>>>> Then when I do:
>>>>>
>>>>> Long aId = 76576; // a valid id for an entity of type Bar
>>>>> Foo foo = em.find(Foo.class, aId); // em is EntityManager
>>>>>
>>>>> an exception is thrown (the root cause seems to be ClassCastException)
>>>>> because the EntityManager tries to return an object of type Bar.
>>>>>
>>>>> What am I doing wrong?
>>>>> --
>>>>> View this message in context:
>>>>> http://www.nabble.com/EntityManager.find-returning-instance-of-wrong-type-tp22367490p22367490.html
>>>>> Sent from the EclipseLink - Users mailing list archive at Nabble.com.
>>>>>
>>>>> _______________________________________________
>>>>> eclipselink-users mailing list
>>>>> eclipselink-users@xxxxxxxxxxx
>>>>> https://dev.eclipse.org/mailman/listinfo/eclipselink-users
>>>>>
>>>> _______________________________________________
>>>> eclipselink-users mailing list
>>>> eclipselink-users@xxxxxxxxxxx
>>>> https://dev.eclipse.org/mailman/listinfo/eclipselink-users
>>>>
>>>>
>>>
>>> --
>>> View this message in context:
>>> http://www.nabble.com/EntityManager.find-returning-instance-of-wrong-type-tp22367490p22371962.html
>>> Sent from the EclipseLink - Users mailing list archive at Nabble.com.
>>>
>>> _______________________________________________
>>> eclipselink-users mailing list
>>> eclipselink-users@xxxxxxxxxxx
>>> https://dev.eclipse.org/mailman/listinfo/eclipselink-users
>>>
>> _______________________________________________
>> eclipselink-users mailing list
>> eclipselink-users@xxxxxxxxxxx
>> https://dev.eclipse.org/mailman/listinfo/eclipselink-users
>>
>>
>
> --
> View this message in context: http://www.nabble.com/EntityManager.find-returning-instance-of-wrong-type-tp22367490p22372894.html
> Sent from the EclipseLink - Users mailing list archive at Nabble.com.
>
> _______________________________________________
> eclipselink-users mailing list
> eclipselink-users@xxxxxxxxxxx
> https://dev.eclipse.org/mailman/listinfo/eclipselink-users
>
