Need help with Hibernate? Read this first:
http://www.hibernate.org/ForumMailingli ... AskForHelp

Hibernate version: 3.0.5

Mapping documents:

First
<class name="User" table="USER">
<id name="userId" column="USER_ID" type="java.lang.Long">
<generator class="assigned"/>
</id>

<property name="password" column="PASSWORD" type="java.lang.String" />
<property name="userName" column="USER_NAME" type="java.lang.String" not-null="true" />

<set name="userGroupHierarchy" lazy="false">
<key column="USER_ID"/>
<one-to-many class="UserGroup"/>
</set>
</class>

Second
<class name="Group" table="GROUP">
<id name="groupId" column="GROUP_ID" type="java.lang.Long">
<generator class="assigned"/>
</id>

<property name="groupName" column="GROUP_NAME" type="java.lang.String" not-null="true" />

<set name="userGroupHierarchy" lazy="false">
<key column="GROUP_ID"/>
<one-to-many class="UserGroup"/>
</set>

</class>
Third
<class name="UserGroup" table="USER_GROUP">
<composite-id name="id" class="UserGroupKey">
<key-many-to-one name="group" column="GROUP_ID" class="Group"/>
<key-many-to-one name="user" column="USER_ID" class="User"/>
</composite-id>

<many-to-one name="user" column="USER_ID" class="User" not-null="true" insert="false" update="false"/>

<many-to-one name="group" column="GROUP_ID" class="Group" not-null="true" insert="false" update="false"/>
</class>


Code between sessionFactory.openSession() and session.close():
Query query = session.createQuery("from User as u where u.userId = ?");

query.setParameter(0,userId);
User user = new User();
List list = query.list();
if(list!=null){
user = (User) list.get(0);
}

Query query2 = session.createQuery("from Group as gs where gs.groupId = ?");

query2.setParameter(0,gId);
Group group = new Group();

List list2 = query2.list();

if(list2!=null){
group = (Group) list2.get(0);
}
Set ugSet = group.getUserGroupHierarchy();
UserGroup groupHierarchy = new UserGroup();
// groupHierarchy.setCreationDate(new Date());
// groupHierarchy.setModifiedDate(new Date());
groupHierarchy.setUser(user);
groupHierarchy.setGroup(group);

UserGroupKey key = new UserGroupKey();

key.setGroup(group);
key.setUser(user);

groupHierarchy.setId(key);

Set userGH = ugSet;

userGH.add(groupHierarchy);
userSecurity.setUserGroup(userGH);

session.saveOrUpdate(userSecurity);
Full stack trace of any exception that occurs:
org.hibernate.HibernateException: Found shared references to a collection
at org.hibernate.engine.Collections.processReachableCollection(Collections.java:130)
at org.hibernate.event.def.FlushVisitor.processCollection(FlushVisitor.java:37)
at org.hibernate.event.def.AbstractVisitor.processValue(AbstractVisitor.java:104)
at org.hibernate.event.def.AbstractVisitor.processValue(AbstractVisitor.java:64)
at org.hibernate.event.def.AbstractVisitor.processEntityPropertyValues(AbstractVisitor.java:58)
at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:198)
at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:190)
at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:70)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:26)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:730)
at com.btwholesale.portal.dua.dao.ESRDAOImpl.updateUserGroup(Unknown Source)
Name and version of the database you are using: Oracle 8i


The problem is occuring as the comosite ID is also a foreign key too 2 different tables and data is to be inserted in table with foreign key.. primary key is already there in table...
USER
userId - PK

GROUP
groupId - pk

USER_GROUP
userId
groupId --composite Id

Please Help!

Note:Some non required entries from mapping have been removed as they are not teh part of the problem

Change your third mapping file. Either you will have this mapping file



or



The second approach is preferable for now as per documentation. Please see this link http://www.hibernate.org/117.html#A34

sorry this did't helped, now i got
Hibernate: update USER_GROUP set USER_ID=null where USER_ID=?
- SQL Error: 1407, SQLState: 72000
- ORA-01407: cannot update ("WLP_USER"."USER_GROUP"."USER_ID") to NULL

- SQL Error: 1407, SQLState: 72000
- ORA-01407: cannot update ("WLP_USER"."USER_GROUP"."USER_ID") to NULL


I get the Set of UserGroup from first User Table and added one more row to it and tried to update.! it is making them null??[/code]

Actually there is an error in the second form of mapping file. I reused the name attributes which should be different. I hope you have the corrected one in your file.

the variable names is not an issue both were in different files,
UserGroup and UserGroupKey.

Even i am facing the same issue.
If someone can come up with solution,that will be of great help.

however I try to understand, these lines are confusing me. Could you explain in words what you are trying to achieve.

The scenario is like this.
UserId's are in USER table
GroupId's are in GROUP table

i have to add user to some group...

this user is already in some other group...

so, there is already some entry for that user in USER_GROUP table

I made a query on GROUP table and get a Set of entries in USER_GROUP table(one to many),



then i added another object in this Set,



to remove the issue of shared references i copied all the Set entries in some other Set,



and save() the USER table with new Set formed (with new entry).

Since the composite id of USER_GROUP table is also a foreign key,
i gave the reference of same User object.



As per your advice i modified the third mapping file, but during update the hibernate tries to set null in existing data in USER_GROUP.

Can anyone please help on this.
Even i am facing the same issue.