many-to-many relation with xdoclet

[eddie07]

I am not able to use xdoclet tags to generate the correct jbosscmp-jdbc.xml file for a (bidirectional) m-n-relation.

This is what I am testing, but jbosscmp-jdbc.xml is not generated (unfortunately without an error message, I am using eclipse).
part of the code:
EBUserBean:

/**
* @ejb.bean name="EBUser"
* jndi-name="EBUserTestBean"
* type="CMP"
* primkey-field="user_id"
* schema="UserSchema"
* cmp-version="2.x"
*
* @ejb.persistence
* table-name="USERS"
**/
...
public abstract class EBUserBean implements EntityBean {

...

/**
* @ejb.interface-method
*
* @ejb.relation
* name="UserGroupRelation"
* role-name="UserhasGroups"
* target-role-name="GroupsForUser"
* target-ejb="EBGroup"
*
* @jboss.relation-mapping style="relation-table"
*
* @jboss.relation-table table-name="USERGROUPRELATION"
*
* @jboss.relation related-pk-field = "group_id"
* fk-column = "USER_ID"
*
*/

public abstract java.util.Collection getGroups();
public abstract void setGroups(java.util.Collection groups);

EBGroupBean:

/**
* @ejb.bean name="EBGroup"
* jndi-name="EBGroupBean"
* type="CMP"
* primkey-field="group_id"
* schema="GroupSchema"
* cmp-version="2.x"
*
* @ejb.persistence
* table-name="GROUPS"
*
**/
...
public abstract class EBGroupBean implements EntityBean {

...

/**
* @ejb.interface-method
*
* @ejb.relation
* name="UserGroupRelation"
* role-name="GroupsForUser"
* target-role-name="UserhasGroups"
* target-ejb="EBUser"
*
* @jboss.relation-table table-name="USERGROUPRELATION"
*
* @jboss.relation related-pk-field = "user_id"
* fk-column = "GROUP_ID"
*
*/

public abstract java.util.Collection getUsers();
public abstract void setUsers(java.util.Collection users);



It's working for a unidirectional relation:

EBUserBean:

/**
* @ejb.interface-method
*
* @ejb.relation
* name="UserGroupRelation"
* role-name="UserhasGroups"
* target-role-name="GroupsForUser"
* target-ejb="EBGroup"
*
* @jboss.relation-mapping style="relation-table"
*
* @jboss.relation-table table-name="USERGROUPRELATION"
*
* @jboss.relation related-pk-field = "group_id"
* fk-column = "USER_ID"
*
* @jboss.target-relation related-pk-field = "user_id"
* fk-column = "GROUP_ID"
*
*/

public abstract java.util.Collection getGroups();
public abstract void setGroups(java.util.Collection groups);


EBGroupBean:

/**
* @ejb.interface-method
*
*/

public abstract java.util.Collection getUsers();
public abstract void setUsers(java.util.Collection users);

What am I doing wrong here?
Or can someone show me a working example?

BTW, the same problem occurs for a 1-n relation, I am only able to use it unidirectional.

Eddie

[raja05]

target-* should occur only if the relation is Unidirectional.

<from_xdoclet>
target-role-name text Name of the relationship role on the other side of the relation. Should *only* occur if the relation is unidirectional.
</from_xdoclet>

Remove the target_role_name and target_ejb ..

-Raj

[eddie07]

Thanks for your answer.

> Remove the target_role_name and target_ejb ..

I tried this also, but still the xml file is not generated. These are my actual tags:

EBUserBean:
/**
* @ejb.interface-method
*
* @ejb.relation
* name="UserGroupRelation"
* role-name="UserhasGroups"
*
* @jboss.relation-mapping style="relation-table"
*
* @jboss.relation-table table-name="EDDIEUSERGROUPRELATION"
*
* @jboss.relation related-pk-field = "group_id"
* fk-column = "USER_ID"
*
*/

EBGroupBean:
/**
* @ejb.interface-method
*
* @ejb.relation
* name="UserGroupRelation"
* role-name="GroupsForUser"
*
* @jboss.relation-mapping style="relation-table"
*
* @jboss.relation-table table-name="EDDIEUSERGROUPRELATION"
*
* @jboss.relation related-pk-field = "user_id"
* fk-column = "GROUP_ID"
*
*/

I also tried to use jboss.relation-mapping and jboss.relation-table only in one of the beans.

Eddie

[raja05]

Hi Eddie,
This is from a sample code. The relation isbetween Employees and Projects (m * n)
/** Employee Bean **/
/**
* @ejb.interface-method
* @ejb.relation name="employee-projects"
* role-name="employee-belongs-to-projects"
*
* @jboss.relation related-pk-field="projectID"
* fk-column="ProjectID"
*
* @jboss.relation-table table-name="T_EMPLOYEE_PROJECTS"
* create-table="true"
* remove-table="true"
*/
public abstract Collection getProjects();


/** Project Bean **/
/**
* @ejb.interface-method
* @ejb.relation name="employee-projects"
* role-name="project-has-employees"
*
* @jboss.relation related-pk-field="empID"
* fk-column="EmployeeID"
*
* @jboss.relation-table table-name="T_EMPLOYEE_PROJECTS"
* create-table="true"
* remove-table="true"
*/
public abstract Collection getEmployees();

[eddie07]

> This is from a sample code. The relation isbetween
> Employees and Projects (m * n)

Now I am totally confused. I am doing exactly the same (even the order of the tags, blanks, ...) but it doesn't work for me. No idea what the problem could be. :-(
Nevertheless thanks for your samples. Now I know at least the direction.

Eddie

[raja05]

i use XDoclet 1.1b2(I think!!)
If you want, i can run XDoclet on your classes, can you send me ur beans , just these two beans to
raja05 at yahoo dot com

Cheers
Raj

[bartekk]

Hi Eddie,
I had the same problem. I think it's xdoclet (or Lomboz xdoclet configuration) bug
I'm using Eclipse with Lomboz plugin and XDoclet 1.2b3 with JBoss3.2.1.

I've found the reason:

--- Nested Exception ---
xdoclet.XDocletException: The relation FunkcjaInAGrupaFunkcjiRelation seems to be many-to-many (m:n). You should therefore specify weblogic:relation join-table-name="blabla".

(I'm using JBoss and I have no idea why should I specyfy weblogic tag - It's a bug I think!)

Add xdoclet tag:
@weblogic.relation join-table-name="blabla"
and it will be working.

regards
Bart