[Hibernate Tools] remove one-to-many relations

zero · **Joined:** Wed Jul 19, 2006 4:05 am **Posts:** 13

Hi,

Hibernate version: 3.1.3

JBoss IDE version: 2.0.0Alpha

I use the Hibernate Code Generation with a reveng.xml and a reveng. strategy files.

Hibernate Tools generates the many-to-one relations well. But, I would like to prevent the generation of the (reverse) one-to-many relations. How can I do this please ?

Thx,

Jake123 · **Posted:** Fri Aug 04, 2006 4:46 pm

Hi,
Lets say that you have two tables, APP_USER and APP_USER_ROLE where a AppUser object can have a Set of AppUserRole (this is the correct mapping) and Hibernate tools will generate a AppUser as a private member in ApPUserRole. This is the relationship that you whant to delete. Right?

the solution is to put some xml in your reveng.xml file.

Code:

   <table schema="MYSCHEMA" name="APP_USER_ROLE">
      <foreign-key constraint-name="FK_APP_USER_APP_USER_ROLE">
         <many-to-one property="AppUser" exclude="true" />
      </foreign-key>
   </table>

where constraint-name is the name for the foreign key relationship between the two tables. Many-to-one property is the name of the property that Hibernate creates in your AppUserRole. In this case AppUser.

Table schema and name I do not need to explain....

Cheers,
Jacob

max · **Posted:** Sat Aug 05, 2006 2:22 am

fastest way is to implement a custom reverese engineering class and return false for excludeForeignKeyAsCollection then no one-to-many will be created.

zero · **Joined:** Wed Jul 19, 2006 4:05 am **Posts:** 13

Jake123 wrote:

the solution is to put some xml in your reveng.xml file.

Code:

   <table schema="MYSCHEMA" name="APP_USER_ROLE">
      <foreign-key constraint-name="FK_APP_USER_APP_USER_ROLE">
         <many-to-one property="AppUser" exclude="true" />
      </foreign-key>
   </table>

The right solution is in the reveng.xml file. But the exact syntax is :

Code:

   <table schema="MYSCHEMA" name="APP_USER_ROLE">
      <foreign-key constraint-name="FK_APP_USER_APP_USER_ROLE">
         <set property="AppUser" exclude="true" />
      </foreign-key>
   </table>

Thanks a lot for your help. My problem is solved !

zero · **Joined:** Wed Jul 19, 2006 4:05 am **Posts:** 13

max wrote:

fastest way is to implement a custom reverese engineering class and return false for excludeForeignKeyAsCollection then no one-to-many will be created.

I thought to use the DelegatingReverseEngineeringStrategy.excludeForeignKeyCollection() method. Because is it the fastest way.
But this method is never called in my custom reverse engineering strategy. :-/

max · **Posted:** Mon Aug 07, 2006 8:19 am

show me your code for the custom strategy and how you set it up.

zero · **Joined:** Wed Jul 19, 2006 4:05 am **Posts:** 13

Sorry Max,

I've just realised that I wrote a (beginner) error :

Code:

   public boolean excludeForeignKeyCollection(String keyname, TableIdentifier fromTable, List fromColumns, TableIdentifier referencedTable, List referencedColumns) {
      return true;
   } 

The right code is :

Code:

   public boolean excludeForeignKeyAsCollection(String keyname, TableIdentifier fromTable, List fromColumns, TableIdentifier referencedTable, List referencedColumns) {
      return true;
   }

I implemented the excludeForeignKeyCollection() methode instead of excludeForeignKeyAsCollection(). Whereas I did a call to the good super.excludeForeignKeyAsCollection() method !

Thanks again to Max and Jacob !

zero · **Joined:** Wed Jul 19, 2006 4:05 am **Posts:** 13

I cannot give two rates when users give me two solutions ?

max · **Posted:** Mon Aug 07, 2006 10:45 am

you can only rate a certain number of times in one thread....can't remember how many though.

zero · **Joined:** Wed Jul 19, 2006 4:05 am **Posts:** 13

I rated the Jacod reply. But now, I cannot rate your reply. :-(

max · **Posted:** Mon Aug 07, 2006 10:58 am

I'll survive :)

(but you should be able to rate 3 times per thread)

adrian.fedoreanu · **Joined:** Fri Dec 04, 2009 4:34 am **Posts:** 1

Hi,

I have a similar situation, I want to exclude some of the inverse sets from my mapping files, like the one below:

Code:

        <set name="rumWayLineMultiples" inverse="true">
            <key>
                <column name="ID_HIERACHY_LISTE" precision="22" scale="0" not-null="true" />
            </key>
            <one-to-many class="com.test.model.RumWayLineMultiple" />
        </set>

So in my RevengStrategy.java I've overridden the excludeForeignKeyAsCollection() method like this :

Code:

   public boolean excludeForeignKeyAsCollection(String FK, TableIdentifier tableIdentifier, List list, TableIdentifier tableIdentifier1, List list1) {
   boolean collectionInverse = isForeignKeyCollectionInverse(FK, tableIdentifier, list, tableIdentifier1, list1);
        if(collectionInverse) {
            return true;
        }
        return false;
    }

But this doesn't work quite the way I expected. It removes all the <sets> but it also removes some <many-to-one> mappings.
There is another method excludeForeignKeyAsManytoOne() and I thought that this handles <many-to-one>.

Any ideas why it does that ? And is it possible to exclude only certain <sets> ? I mean if a mapping file has 3 <sets>, can I tell excludeForeignKeyAsCollection() based on the foreign key or tables identifiers exactly which <sets> I want excluded ?

Thanks