I want to implement this,two discriminator subclass,there is a one-to-one relation between two subclass,but It is a legacy schema,two subclass is in one table.
In detail,
Hibernate version:2.1.6


<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="com.caec.amis.model.DynFlight" table="dynflight" schema="dbo" dynamic-update = "true" dynamic-insert = "true">
<id name="flightid" type="long" column="flightid" unsaved-value="null" length="8">
<generator class="assigned"/>
</id>
<discriminator column="inoutflag" not-null="true" type="string" length="2"/>
<property name="execdate" type="timestamp"
column="execdate" not-null="true" length="23"/>


<property name="lightinguse" type="string" column="lightinguse" length="1"/>


<subclass name="com.caec.amis.model.ArrvialDynFlight" discriminator-value="A">
<one-to-one name="associateflight" foreign-key="fkarrvialtodepartflight" class="com.caec.amis.model.DepartDynFlight" cascade="all" constrained="true"/>
</subclass>
<subclass name="com.caec.amis.model.DepartDynFlight" discriminator-value="D">

<one-to-one name="associateflight" foreign-key="fkdeparttoarrvialflight" class="com.caec.amis.model.ArrvialDynFlight" cascade="all" constrained="true"/>

</subclass>







</class>
</hibernate-mapping>

java code:(using spring 1.1 final)

ArrvialDynFlight af = new ArrvialDynFlight();
af.setFlightid(new Long(1));
af.setExecdate(new Date());
af.setLightinguse("2");

DepartDynFlight df = new DepartDynFlight();
df.setFlightid(new Long(2));
df.setExecdate(new Date());
df.setLightinguse("3");
af.setAssociateflight(df);
df.setAssociateflight(af);
this.getHibernateTemplate().save(af);


debug info:
log4j:WARN No appenders could be found for logger (org.springframework.beans.factory.xml.XmlBeanDefinitionReader).
log4j:WARN Please initialize the log4j system properly.
org.springframework.orm.hibernate.HibernateSystemException: SQL insert, update or delete failed (row not found); nested exception is net.sf.hibernate.HibernateException: SQL insert, update or delete failed (row not found)
net.sf.hibernate.HibernateException: SQL insert, update or delete failed (row not found)
at net.sf.hibernate.impl.NonBatchingBatcher.addToBatch(NonBatchingBatcher.java:25)
at net.sf.hibernate.persister.EntityPersister.update(EntityPersister.java:684)
at net.sf.hibernate.persister.EntityPersister.update(EntityPersister.java:642)
at net.sf.hibernate.impl.ScheduledUpdate.execute(ScheduledUpdate.java:52)
at net.sf.hibernate.impl.SessionImpl.executeAll(SessionImpl.java:2418)
at net.sf.hibernate.impl.SessionImpl.execute(SessionImpl.java:2372)
at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2240)
at net.sf.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:61)
at org.springframework.orm.hibernate.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:460)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:373)
at org.springframework.transaction.interceptor.TransactionAspectSupport.doCommitTransactionAfterReturning(TransactionAspectSupport.java:241)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:66)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:138)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:152)
at $Proxy1.find(Unknown Source)
at com.caec.amis.test.testdao.main(testdao.java:22)
Exception in thread "main"


I am not sure,it is possible?

sorry,Additional information,I use Sybase 12.5 for windows nt.