5:35 a.m.
Hibernate gives a Javaassist object rather than the real object that I need in a subclass
mapping
-------------------------------------------------------------------------------------------------
Key: HHH-4456
URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-4456
Project: Hibernate Core
Issue Type: Bug
Components: core
Affects Versions: 3.3.1
Environment: 3.3.1 ga, hsqldb/mysql
Reporter: Ken Egervari
I have an interesting mapping where the parent class is sub classed and is mapped as
such... and it contains an object that is also sub classed. Because java doesn't have
multiple inheritance, I do this to avoid a wacky exponentially complex inheritance
hierarchy. I would say this is pretty normal domain architecture for the type of problem.
Now, on the inner object, Hibernate is doing the mapping just fine, but when I pull it
from the database and cast it, it throws an example.
{code}
java.lang.ClassCastException:
jawbs.domain.application.questiontype.QuestionType_$$_javassist_7 cannot be cast to
jawbs.domain.application.questiontype.MultipleChoiceType
at jawbs.dao.QuestionDaoTest.findJobApplicationQuestion(QuestionDaoTest.java:122)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
...
{code}
The code is just a test case:
{code}
@Test
public void findJobApplicationQuestion() {
JobApplicationQuestion question = ( JobApplicationQuestion )
questionDao.find( 2 );
// THIS IS WHERE THE PROGRAM BOMBS
MultipleChoiceType type = ( MultipleChoiceType ) question.getType();
assertEquals( "What is the namespace for jawbs in JS?", question.getText() );
assertEquals( 1, question.getJob().getId() );
assertEquals( 3, type.getCorrectOption().getId() );
}
{code}
And the mapping is as follows. There are two entities, one containing another... and both
entities are being sub classed.
{code?xml}
<class name="jawbs.domain.application.Question"
table="question" abstract="true">
<id name="id" column="question_id"
type="long">
<generator class="native"/>
</id>
<discriminator column="application_type"
type="string"/>
<property name="text" type="text" />
<many-to-one name="type"
class="jawbs.domain.application.questiontype.QuestionType"
column="question_type_id" />
<subclass name="jawbs.domain.application.JobApplicationQuestion"
discriminator-value="JOB">
<many-to-one name="job" class="jawbs.domain.job.Job"
column="job_id"/>
</subclass>
<subclass
name="jawbs.domain.application.ScholarshipApplicationQuestion"
discriminator-value="SCHOLARSHIP">
<many-to-one name="employer"
class="jawbs.domain.employer.Employer"
column="employer_id"/>
</subclass>
</class>
<class name="jawbs.domain.application.questiontype.QuestionType"
table="question_type" abstract="true">
<id name="id" column="question_type_id"
type="long">
<generator class="native"/>
</id>
<discriminator column="type" type="string"/>
<many-to-one name="question"
class="jawbs.domain.application.Question"
column="question_id"/>
<subclass name="jawbs.domain.application.questiontype.TrueFalseType"
discriminator-value="TRUE_FALSE">
<property name="correctChoice" column="correct_choice"
/>
</subclass>
<subclass
name="jawbs.domain.application.questiontype.MultipleChoiceType"
discriminator-value="MULTIPLE_CHOICE">
<many-to-one name="correctOption"
class="jawbs.domain.application.questiontype.MultipleChoiceOption"
column="correct_option_id"/>
</subclass>
<subclass name="jawbs.domain.application.questiontype.OpenEndedType"
discriminator-value="OPEN_ENDED">
</subclass>
</class>
{code}
I'd appreciate any assistance. I suspect this is a bug, or maybe I configured it
wrong. The documentation doesn't really include examples like this, so I dunno what to
do to fix it.
Thanks
--
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
http://opensource.atlassian.com/projects/hibernate/secure/Administrators....
-
For more information on JIRA, see: http://www.atlassian.com/software/jira