I am trying to implement unidirection one-to-many with a join table
I have Hibernate 3.2.6, Oracle 10g, JDK 1.5

tables and the key columns: (PK:Primary Key, FK:Foreign Key)
TM_CAMPAIGN:
CAMP_ID (PK) not null
TM_CAMP_JOINT_EMAIL_BODY:
CAMP_ID (FK) not null, <FK: FK_CAMP_JEMB>
EMBD_ID (FK) not null, <FK: FK_EMBD_JEMB>
TM_CAMP_EMAIL_BODY:
EMBD_ID (PK) not null

mapping file:
<hibernate-mapping>
<class name="pw.CampaignDetail" table="TM_CAMPAIGN">
<id name="campId" type="int" column="CAMP_ID">
<generator class="sequence">
<param name="sequence">CAMP_ID</param>
</generator>
</id>
<set name="campaignEmailBodies" table="TM_CAMP_JOINT_EMAIL_BODY" cascade="all">
<key column="CAMP_ID"/>
<many-to-many column="EMBD_ID" unique="true" class="pw.EmailBody"/>
</set>
</class>
<class name="pw.EmailBody" table="TM_CAMP_EMAIL_BODY" >
<id name="emailBodyId" type="int" column="EMBD_ID">
<generator class="sequence">
<param name="sequence">EMBD_ID</param>
</generator>
</id>
</class>
</hibernate-mapping>

java classes:
CampaignDetail.java
private int campId;
private Set<EmailBody> campaignEmailBodies;
getters, setters

EmailBody.java
private int emailBodyId;
getters, setters

test code:
CampaignDetail campDetail = new CampaignDetail();
EmailBody body1 = new EmailBody();
EmailBody body2 = new EmailBody();
campDetail.getCampaignEmailBodies().add(body1);
campDetail.getCampaignEmailBodies().add(body2);

session.beginTransaction();
session.save(campDetail);
session.getTransaction().commit();

When executed, the correct insert commands were generated, but got
java.sql.BatchUpdateException: ORA-02291: integrity constraint (TMTEST.FK_EMBD_JEMB) violated - parent key not found

I appreciate your help!

Following is the more detail debug log:
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Static SQL for entity: pw.EmailBody
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Version select: select EMBD_ID from
……
[main] DEBUG org.hibernate.transaction.JDBCTransaction - begin
[main] DEBUG org.hibernate.jdbc.ConnectionManager - opening JDBC connection
[main] DEBUG org.hibernate.connection.DriverManagerConnectionProvider - total checked-out connections: 0
[main] DEBUG org.hibernate.connection.DriverManagerConnectionProvider - opening new JDBC connection
……
[main] DEBUG org.hibernate.SQL - select CAMP_ID.nextval from dual
Hibernate: select CAMP_ID.nextval from dual
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - preparing statement
[main] DEBUG org.hibernate.id.SequenceGenerator - Sequence identifier generated: 693
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - closing statement
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - generated identifier: 693, using strategy: org.hibernate.id.SequenceGenerator
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - saving [pw.CampaignDetail#693]
[main] DEBUG org.hibernate.engine.Cascade - processing cascade ACTION_SAVE_UPDATE for: pw.CampaignDetail
[main] DEBUG org.hibernate.engine.Cascade - done processing cascade ACTION_SAVE_UPDATE for: pw.CampaignDetail
[main] DEBUG org.hibernate.event.def.WrapVisitor - Wrapped collection in role: pw.CampaignDetail.campaignEmailBodies
[main] DEBUG org.hibernate.engine.Cascade - processing cascade ACTION_SAVE_UPDATE for: pw.CampaignDetail
[main] DEBUG org.hibernate.engine.Cascade - cascade ACTION_SAVE_UPDATE for collection: pw.CampaignDetail.campaignEmailBodies
[main] DEBUG org.hibernate.engine.CascadingAction - cascading to saveOrUpdate: pw.EmailBody
[main] DEBUG org.hibernate.engine.IdentifierValue - id unsaved-value: 0
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - transient instance of: pw.EmailBody
[main] DEBUG org.hibernate.event.def.DefaultSaveOrUpdateEventListener - saving transient instance
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to open PreparedStatement (open PreparedStatements: 0, globally: 0)
[main] DEBUG org.hibernate.SQL - select EMBD_ID.nextval from dual
Hibernate: select EMBD_ID.nextval from dual
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - preparing statement
[main] DEBUG org.hibernate.id.SequenceGenerator - Sequence identifier generated: 461
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - closing statement
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - generated identifier: 461, using strategy: org.hibernate.id.SequenceGenerator
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - saving [pw.EmailBody#461]
[main] DEBUG org.hibernate.engine.CascadingAction - cascading to saveOrUpdate: pw.EmailBody
[main] DEBUG org.hibernate.engine.IdentifierValue - id unsaved-value: 0
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - transient instance of: pw.EmailBody
[main] DEBUG org.hibernate.event.def.DefaultSaveOrUpdateEventListener - saving transient instance
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to open PreparedStatement (open PreparedStatements: 0, globally: 0)
[main] DEBUG org.hibernate.SQL - select EMBD_ID.nextval from dual
Hibernate: select EMBD_ID.nextval from dual
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - preparing statement
[main] DEBUG org.hibernate.id.SequenceGenerator - Sequence identifier generated: 462
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - closing statement
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - generated identifier: 462, using strategy: org.hibernate.id.SequenceGenerator
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - saving [pw.EmailBody#462]
[main] DEBUG org.hibernate.engine.Cascade - done cascade ACTION_SAVE_UPDATE for collection: pw.CampaignDetail.campaignEmailBodies
[main] DEBUG org.hibernate.engine.Cascade - done processing cascade ACTION_SAVE_UPDATE for: pw.CampaignDetail
[main] DEBUG org.hibernate.transaction.JDBCTransaction - commit
[main] DEBUG org.hibernate.impl.SessionImpl - automatically flushing session
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - flushing session
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - processing flush-time cascades
[main] DEBUG org.hibernate.engine.Cascade - processing cascade ACTION_SAVE_UPDATE for: pw.CampaignDetail
[main] DEBUG org.hibernate.engine.Cascade - cascade ACTION_SAVE_UPDATE for collection: pw.CampaignDetail.campaignEmailBodies
[main] DEBUG org.hibernate.engine.CascadingAction - cascading to saveOrUpdate: pw.EmailBody
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - persistent instance of: pw.EmailBody
[main] DEBUG org.hibernate.event.def.DefaultSaveOrUpdateEventListener - ignoring persistent instance
[main] DEBUG org.hibernate.event.def.DefaultSaveOrUpdateEventListener - object already associated with session: [pw.EmailBody#461]
[main] DEBUG org.hibernate.engine.CascadingAction - cascading to saveOrUpdate: pw.EmailBody
[main] DEBUG org.hibernate.event.def.AbstractSaveEventListener - persistent instance of: pw.EmailBody
[main] DEBUG org.hibernate.event.def.DefaultSaveOrUpdateEventListener - ignoring persistent instance
[main] DEBUG org.hibernate.event.def.DefaultSaveOrUpdateEventListener - object already associated with session: [pw.EmailBody#462]
[main] DEBUG org.hibernate.engine.Cascade - done cascade ACTION_SAVE_UPDATE for collection: pw.CampaignDetail.campaignEmailBodies
[main] DEBUG org.hibernate.engine.Cascade - done processing cascade ACTION_SAVE_UPDATE for: pw.CampaignDetail
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - dirty checking collections
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - Flushing entities and processing referenced collections
[main] DEBUG org.hibernate.engine.Collections - Collection found: [pw.CampaignDetail.campaignEmailBodies#693], was: [<unreferenced>] (initialized)
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - Processing unreferenced collections
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - Scheduling collection removes/(re)creates/updates
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - Flushed: 3 insertions, 0 updates, 0 deletions to 3 objects
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - Flushed: 1 (re)creations, 0 updates, 0 removals to 1 collections
[main] DEBUG org.hibernate.pretty.Printer - listing entities:
[main] DEBUG org.hibernate.pretty.Printer - pw.EmailBody{emailBodyId=461, emailContentType=text/html, emailBody=camp2 emailBody is clob - text/html}
[main] DEBUG org.hibernate.pretty.Printer - pw.EmailBody{emailBodyId=462, emailContentType=text/plain, emailBody=camp2 emailBody is clob - text/plain}
[main] DEBUG org.hibernate.pretty.Printer - pw.CampaignDetail{…, campaignEmailBodies=[pw.EmailBody#461, pw.EmailBody#462], …}
[main] DEBUG org.hibernate.event.def.AbstractFlushingEventListener - executing flush
[main] DEBUG org.hibernate.jdbc.ConnectionManager - registering flush begin
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Inserting entity: [pw.CampaignDetail#693]
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to open PreparedStatement (open PreparedStatements: 0, globally: 0)
[main] DEBUG org.hibernate.SQL - insert into TM_CAMPAIGN (CAMP_NAME, CAMP_DESC, CAMP_SQL_CONDITION, CAMP_FROM_EMAIL_ADDRESS, CAMP_FROM_NAME, CHAR_CODE, CAMP_EMAIL_SUBJECT, CAMP_IS_ACTIVE, CAMP_IS_EDITOR, CAMP_IS_SALON_CLIENT, CAMP_IS_WEB_CLIENT, CAMP_IS_COUNTER_CLIENT, CAMP_ID) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?) …
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - preparing statement
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Dehydrating entity: [pw.CampaignDetail#693]
[main] DEBUG org.hibernate.type.StringType - binding 'camp2 camp name' to parameter: 1
……
[main] DEBUG org.hibernate.type.IntegerType - binding '693' to parameter: 13
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Inserting entity: [pw.EmailBody#461]
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - Executing batch size: 1
[main] DEBUG org.hibernate.jdbc.Expectations - success of batch update unknown: 0
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - closing statement
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to open PreparedStatement (open PreparedStatements: 0, globally: 0)
[main] DEBUG org.hibernate.SQL - insert into TM_CAMP_EMAIL_BODY (EMBD_CONTENT_TYPE, EMBD_BODY, EMBD_ID) values (?, ?, ?)
Hibernate: insert into TM_CAMP_EMAIL_BODY (EMBD_CONTENT_TYPE, EMBD_BODY, EMBD_ID) values (?, ?, ?)
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - preparing statement
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Dehydrating entity: [pw.EmailBody#461]
[main] DEBUG org.hibernate.type.StringType - binding 'text/html' to parameter: 1
[main] DEBUG org.hibernate.type.StringType - binding 'camp2 emailBody is clob - text/html' to parameter: 2
[main] DEBUG org.hibernate.type.IntegerType - binding '461' to parameter: 3
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Inserting entity: [pw.EmailBody#462]
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - reusing prepared statement
[main] DEBUG org.hibernate.SQL - insert into TM_CAMP_EMAIL_BODY (EMBD_CONTENT_TYPE, EMBD_BODY, EMBD_ID) values (?, ?, ?) …
[main] DEBUG org.hibernate.persister.entity.AbstractEntityPersister - Dehydrating entity: [pw.EmailBody#462]
[main] DEBUG org.hibernate.type.StringType - binding 'text/plain' to parameter: 1
[main] DEBUG org.hibernate.type.StringType - binding 'camp2 emailBody is clob - text/plain' to parameter: 2
[main] DEBUG org.hibernate.type.IntegerType - binding '462' to parameter: 3
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - Executing batch size: 2
[main] DEBUG org.hibernate.jdbc.Expectations - success of batch update unknown: 0
[main] DEBUG org.hibernate.jdbc.Expectations - success of batch update unknown: 1
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - closing statement
[main] DEBUG org.hibernate.persister.collection.AbstractCollectionPersister - Inserting collection: [pw.CampaignDetail.campaignEmailBodies#693]
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to open PreparedStatement (open PreparedStatements: 0, globally: 0)
[main] DEBUG org.hibernate.SQL - insert into TM_CAMP_JOINT_EMAIL_BODY (CAMP_ID, EMBD_ID) values (?, ?) …
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - preparing statement
[main] DEBUG org.hibernate.type.IntegerType - binding '693' to parameter: 1
[main] DEBUG org.hibernate.type.IntegerType - binding '461' to parameter: 2
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - reusing prepared statement
[main] DEBUG org.hibernate.SQL - insert into TM_CAMP_JOINT_EMAIL_BODY (CAMP_ID, EMBD_ID) values (?, ?) …
[main] DEBUG org.hibernate.type.IntegerType - binding '693' to parameter: 1
[main] DEBUG org.hibernate.type.IntegerType - binding '462' to parameter: 2
[main] DEBUG org.hibernate.persister.collection.AbstractCollectionPersister - done inserting collection: 2 rows inserted
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - Executing batch size: 2
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
[main] DEBUG org.hibernate.jdbc.AbstractBatcher - closing statement
[main] DEBUG org.hibernate.util.JDBCExceptionReporter - Could not execute JDBC batch update [insert into TM_CAMP_JOINT_EMAIL_BODY (CAMP_ID, EMBD_ID) values (?, ?)]
java.sql.BatchUpdateException: ORA-02291: integrity constraint (TMTEST.FK_EMBD_JEMB) violated - parent key not found

at oracle.jdbc.driver.DatabaseError.throwBatchUpdateException(DatabaseError.java:498)
at oracle.jdbc.driver.OraclePreparedStatement.executeBatch(OraclePreparedStatement.java:12368)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:48)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:246)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:171)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:298)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:338)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:106)
at pw.TmDAO.commit(TmDAO.java:30)
at pw.TmCampaignDAO.addCampaign(TmCampaignDAO.java:180)
at pw.TestDAOClient.testAddUpdateCampaign(TestDAOClient.java:114)
at pw.TestDAOClient.main(TestDAOClient.java:36)
……