Hibernate version: 2.1.7

I have a strange exception with a many-to-many mapping when saving my objects.

I have a user class with a list of projects and and project class with a list of users.

Mapping documents:

Project:

<hibernate-mapping>

<class name="com.pm.core.domain.project.BasicProjectImpl" table="PROJECT">

<id name="id" column="ID" type="int" unsaved-value="0">
<generator class="native" />
</id>

<version column="VERSION" name="Version" type="long" />

<property name="code" column="CODE" type="string" not-null="true" />
<property name="name" column="NAME" type="string" not-null="true" />

<set name="members" table="member" cascade="none" lazy="false">
<key column="ID" />
<many-to-many column="PMU_ID" class="com.pm.core.domain.UserImpl" outer-join="false"/>
</set>

</class>


User :


<class name="com.pm.core.domain.UserImpl" table="PMUSER">

<id column="ID" name="Id" type="int" unsaved-value="0">
<generator class="native" />
</id>

<version column="VERSION" name="Version" type="long" />

<property column="PWD" length="10" name="Password" not-null="true" type="string" />
<property column="LOGIN" length="10" name="Login" not-null="true" type="string" />
<property column="LASTNAME" length="100" name="LastName" not-null="false" type="string" />
<property column="FIRSTNAME" length="100" name="FirstName" not-null="false" type="string" />
<property column="EMAIL" length="50" name="Email" not-null="true" type="string" />

<many-to-one class="com.pm.core.domain.CompanyImpl" name="Company"
outer-join="true" cascade="none" update="false" insert="false">
<column name="COM_ID" />
</many-to-one>

<set name="projects" table="member" cascade="none" lazy="false">
<key column="PMU_ID" />
<many-to-many column="ID" class="com.pm.core.domain.project.BasicProjectImpl" outer-join="false"/>
</set>

</class>




Full stack trace of any exception that occurs:

When saving a project the trace is:

org.springframework.orm.hibernate.HibernateSystemException: IllegalArgumentException occurred calling getter of com.pm.core.domain.project.BasicProjectImpl.id; nested exception is net.sf.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of com.pm.core.domain.project.BasicProjectImpl.id
net.sf.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of com.pm.core.domain.project.BasicProjectImpl.id
at net.sf.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:110)
at net.sf.hibernate.persister.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:315)
at net.sf.hibernate.proxy.HibernateProxyHelper.getIdentifier(HibernateProxyHelper.java:48)
at net.sf.hibernate.type.EntityType.toString(EntityType.java:84)
at net.sf.hibernate.type.PersistentCollectionType.toString(PersistentCollectionType.java:82)
at net.sf.hibernate.impl.Printer.toString(Printer.java:49)
at net.sf.hibernate.impl.Printer.toString(Printer.java:82)
at net.sf.hibernate.impl.SessionImpl.flushEverything(SessionImpl.java:2301)
at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2259)
at net.sf.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:61)
at org.springframework.orm.hibernate.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:464)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:376)
at org.springframework.transaction.interceptor.TransactionAspectSupport.doCommitTransactionAfterReturning(TransactionAspectSupport.java:242)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:66)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:144)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:174)
at $Proxy0.add(Unknown Source)
at com.pm.core.data.UserMapperTest.testAddWithoutConcurrencyFailureException(UserMapperTest.java:123)
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:585)
at junit.framework.TestCase.runTest(TestCase.java:154)
at junit.framework.TestCase.runBare(TestCase.java:127)
at junit.framework.TestResult$1.protect(TestResult.java:106)
at junit.framework.TestResult.runProtected(TestResult.java:124)
at junit.framework.TestResult.run(TestResult.java:109)
at junit.framework.TestCase.run(TestCase.java:118)
at junit.framework.TestSuite.runTest(TestSuite.java:208)
at junit.framework.TestSuite.run(TestSuite.java:203)
at junit.framework.TestSuite.runTest(TestSuite.java:208)
at junit.framework.TestSuite.run(TestSuite.java:203)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:421)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:305)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:186)
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
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:585)
at net.sf.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:96)
... 34 more




When saving a user the trace is:


org.springframework.orm.hibernate.HibernateSystemException: IllegalArgumentException occurred calling getter of com.pm.core.domain.UserImpl.Id; nested exception is net.sf.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of com.pm.core.domain.UserImpl.Id
net.sf.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of com.pm.core.domain.UserImpl.Id
at net.sf.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:110)
at net.sf.hibernate.persister.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:315)
at net.sf.hibernate.proxy.HibernateProxyHelper.getIdentifier(HibernateProxyHelper.java:48)
at net.sf.hibernate.type.EntityType.toString(EntityType.java:84)
at net.sf.hibernate.type.PersistentCollectionType.toString(PersistentCollectionType.java:82)
at net.sf.hibernate.impl.Printer.toString(Printer.java:49)
at net.sf.hibernate.impl.Printer.toString(Printer.java:82)
at net.sf.hibernate.impl.SessionImpl.flushEverything(SessionImpl.java:2301)
at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2259)
at net.sf.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:61)
at org.springframework.orm.hibernate.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:464)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:376)
at org.springframework.transaction.interceptor.TransactionAspectSupport.doCommitTransactionAfterReturning(TransactionAspectSupport.java:242)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:66)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:144)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:174)
at $Proxy3.add(Unknown Source)
at com.pm.core.data.poject.BasicProjectMapperTest.testAddWithoutConcurrencyFailureException(BasicProjectMapperTest.java:101)
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:585)
at junit.framework.TestCase.runTest(TestCase.java:154)
at junit.framework.TestCase.runBare(TestCase.java:127)
at junit.framework.TestResult$1.protect(TestResult.java:106)
at junit.framework.TestResult.runProtected(TestResult.java:124)
at junit.framework.TestResult.run(TestResult.java:109)
at junit.framework.TestCase.run(TestCase.java:118)
at junit.framework.TestSuite.runTest(TestSuite.java:208)
at junit.framework.TestSuite.run(TestSuite.java:203)
at junit.framework.TestSuite.runTest(TestSuite.java:208)
at junit.framework.TestSuite.run(TestSuite.java:203)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:421)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:305)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:186)
Caused by: java.lang.IllegalArgumentException: java.lang.ClassCastException@739f3f
at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at net.sf.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:96)
... 34 more


Name and version of the database you are using:

MySQL 4.1.18

The generated SQL (show_sql=true):

Debug level Hibernate log excerpt:

I'm having the samething, I think is a misconfiguration of abstract class and/or inheritance which may be causing the problem