Recursive CMR

[ddurst1]

Can someone show me an example of how to do a recursive CMR?

Here is what I have but JBoss is barfing.

<ejb-relation>
<ejb-relation-name>Domain has parent domain</ejb-relation-name>
<ejb-relationship-role>
<ejb-relationship-role-name>DomainEJB</ejb-relationship-role-name>
Many
<relationship-role-source><ejb-name>DomainEJB</ejb-name></relationship-role-source>
<cmr-field>
<cmr-field-name>subDomains</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>DomainEJB</ejb-relationship-role-name>
One
<relationship-role-source><ejb-name>DomainEJB</ejb-name></relationship-role-source>
<cmr-field><cmr-field-name>parentDomain</cmr-field-name></cmr-field>
</ejb-relationship-role>
</ejb-relation>

[ddurst1]

Does anyone actually use this forum to reply, or do people just post and never get any replies?

[darranl]

No people generaly do reply if they understand the question and have an answer to it.

[thammoud]

In my experience the CMP forum is the worst when it comes to getting responses. The best is the cluster forum.

[raja05]

Here is what i have as a developer-manager relationship in the same table.
Employee {
empid,
age,
blah blah,
managerid references empid
}

ejb-jar.xml
<ejb-relation >
<ejb-relation-name>developer-manager</ejb-relation-name>

<ejb-relationship-role >
<ejb-relationship-role-name>developer-assigned-to-manager</ejb-relationship-role-name>
Many
<relationship-role-source >
<ejb-name>Employee</ejb-name>
</relationship-role-source>
<cmr-field >
<cmr-field-name>manager</cmr-field-name>
</cmr-field>
</ejb-relationship-role>

<ejb-relationship-role >
<ejb-relationship-role-name>manager-has-employees</ejb-relationship-role-name>
One
<relationship-role-source >
<ejb-name>Employee</ejb-name>
</relationship-role-source>
</ejb-relationship-role>

</ejb-relation>


jbosscmp-jdbc.xml

<ejb-relation>
<ejb-relation-name>developer-manager</ejb-relation-name>

<foreign-key-mapping/>

<ejb-relationship-role>
<ejb-relationship-role-name>developer-assigned-to-manager</ejb-relationship-role-name>
<fk-constraint>true</fk-constraint>
<key-fields/>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>manager-has-employees</ejb-relationship-role-name>
<key-fields>
<key-field>
<field-name>empID</field-name>
<column-name>manager</column-name>
</key-field>
</key-fields>
</ejb-relationship-role>
</ejb-relation>

Hope this is what you are looking for

-Raj

[jonmartin]

I take it your recursive relationship is a tree-like structure. I use JDeveloper to develop my ejb's, and it works just fine for stuff like this. I struggled quite a lot defining recursive cmr manually a year ago, and finally gave up. Didn't get a reasonable answer on any forum or newsgroup either. Well, anyway, here is my ejb-jar.xml stuff:

<ejb-relation>
<ejb-relation-name>ThemeHierarchy</ejb-relation-name>
<ejb-relationship-role>
<ejb-relationship-role-name>ThemeHasChildren</ejb-relationship-role-name>
One
<relationship-role-source>
<ejb-name>EntTheme</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>children</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>ThemeHasParent</ejb-relationship-role-name>
Many
<cascade-delete/>
<relationship-role-source>
<ejb-name>EntTheme</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>parent</cmr-field-name>
</cmr-field>
</ejb-relationship-role>
</ejb-relation>

While I'm editing this in the tiny little textbox editor I can't really say how this differ from your xml, maybe I'lls ee it after I've posted :-) And I'm running on 3.0.6, 3.0.7 and 3.2.0. It'd also be useful to see the actual error message you get if this doesn't help.

[jonmartin]

Does it work without the cmr-field-type?

[jonmartin]

I try to reply, but I don't see my postings? Is this forum moderated or something?

[jonmartin]

Here is my ejb-jar.xml that works for me. Generally JDeveloper does the job of defining different cmr-stuff well, at least I use it without problems.

It's not needed to define anything in any jboss-specific configuration files, and tables are created where needed by jboss.

<ejb-relation>
<ejb-relation-name>ThemeHierarchy</ejb-relation-name>
<ejb-relationship-role>
<ejb-relationship-role-name>ThemeHasChildren</ejb-relationship-role-name>
One
<relationship-role-source>
<ejb-name>EntTheme</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>children</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>ThemeHasParent</ejb-relationship-role-name>
Many
<cascade-delete/>
<relationship-role-source>
<ejb-name>EntTheme</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>parent</cmr-field-name>
</cmr-field>
</ejb-relationship-role>
</ejb-relation>

[paulward]

Someone already posted a copy of their descriptor, but I thought it might be helpful if someone posted the way one might go about this using the xdoclet tags to do this. Below are the methods that relate to a self-reference of Member to Group

/**
* Get the groups that this destination is a member of
*
* @ejb.interface-method
*
* @ejb.relation name="Destination-Destination"
* role-name="member-has-groups"
*
* @jboss.relation-table table-name="GROUP_MEMBERS"
* create-table="true"
* remove-table="false"
* pk-constraint="true"
*
* @jboss.method-attributes read-only="true"
* @jboss.relation fk-constraint="true"
* fk-column="GROUP_ID"
* related-pk-field="iD"
*
**/
public abstract Set getGroups();

/**
* Set the groups that this destination is a member of
*
* @param groups The new list of groups.
*
**/
public abstract void setGroups(Set groups);

/**
* Get the destinations that are members of this group
*
* @ejb.interface-method
*
* @ejb.relation name="Destination-Destination"
* role-name="group-has-members"
*
* @jboss.relation-table table-name="GROUP_MEMBERS"
* create-table="false"
* remove-table="false"
*
* @jboss.method-attributes read-only="true"
* @jboss.relation fk-constraint="true"
* fk-column="MEMBER_ID"
* related-pk-field="iD"
*
**/
public abstract Set getMembers();

/**
* Set the list of destinations that are members of this group
*
* @param members The new list of members.
*
**/
public abstract void setMembers(Set members);

[paulward]

Someone already posted a copy of their descriptor, but I thought it might be helpful if someone posted the way one might go about this using the xdoclet tags to do this. Below are the methods that relate to a self-reference of Member to Group

/**
* Get the groups that this destination is a member of
*
* @ejb.interface-method
*
* @ejb.relation name="Destination-Destination"
* role-name="member-has-groups"
*
* @jboss.relation-table table-name="GROUP_MEMBERS"
* create-table="true"
* remove-table="false"
* pk-constraint="true"
*
* @jboss.method-attributes read-only="true"
* @jboss.relation fk-constraint="true"
* fk-column="GROUP_ID"
* related-pk-field="iD"
*
**/
public abstract Set getGroups();

/**
* Set the groups that this destination is a member of
*
* @param groups The new list of groups.
*
**/
public abstract void setGroups(Set groups);

/**
* Get the destinations that are members of this group
*
* @ejb.interface-method
*
* @ejb.relation name="Destination-Destination"
* role-name="group-has-members"
*
* @jboss.relation-table table-name="GROUP_MEMBERS"
* create-table="false"
* remove-table="false"
*
* @jboss.method-attributes read-only="true"
* @jboss.relation fk-constraint="true"
* fk-column="MEMBER_ID"
* related-pk-field="iD"
*
**/
public abstract Set getMembers();

/**
* Set the list of destinations that are members of this group
*
* @param members The new list of members.
*
**/
public abstract void setMembers(Set members);