My setup is below. I'm wondering how I can setup a mapping document given the table definitions I have. As you see the JOIN table gems_partner_activity table contains partner_id and activity_id, so that I can specify a bi-directional relationship for both partner and activity relationships (Partner has Activities and Activities have Partners defined).

In addition, however, there are three values in the JOIN table ( hold_transmission, transmit_realtime, and scheduler_name), which belong exclusively to the unique combination of partner and activity combination and they do not make sense outside of that relationship.

How do I create a mapping file to propertly represent them in a Domain Object Model that will be generated?

Here is my setup:

Hibernate version 3.2

DB is MySQL41

Table definitions DDL:
# Partner table definition
CREATE TABLE gems_partner (
partner_id INTEGER NOT NULL,
name VARCHAR(255) NOT NULL,
PRIMARY KEY (partner_id)
);

CREATE TABLE gems_activity (
activity_id INTEGER NOT NULL,
name VARCHAR(255) NOT NULL,
fullpath VARCHAR (255) NOT NULL,
PRIMARY KEY (activity_id)
);

# This is the JOIN table for Activity and Partner
CREATE TABLE gems_partner_activity (
partner_id INTEGER NOT NULL,
activity_id INTEGER NOT NULL,
hold_transmission boolean,
transmit_realtime boolean,
scheduler_name varchar(255),
PRIMARY KEY (partner_id, activity_id),
FOREIGN KEY (partner_id)
REFERENCES gems_partner(partner_id),
FOREIGN KEY (activity_id)
REFERENCES gems_activity(activity_id),
INDEX partner_ind(partner_id),
INDEX activity_ind(activity_id)
);

U can use the below mapping in gemspartner.


mapping of gemspartner

<bag name="links" table="gems_partner_activity" cascade="none">

<column name="partner_id" not-null="true" unique="true" />
</key>
<composite-element class="gemspartneractivity ">
<parent name="partner_id"/>
<property name="hold_transmission" type="string" column="hold_transmission" />
<many-to-one name="activity_id" entity-name="gemsactivity " cascade="none" >
<column name="activity_id" not-null="true" length="30"/>
</many-to-one>
</composite-element>
</bag>

check the model classew also ...

class gemspartner
{
private int partnerid;
private String name;
private Collection links;//collection of ggemspartneractivity objects
//getter and setter
}
class gemsactivity
{
private ... activity_id;
.....
....

private Collection links;//collection of gemspartneractivity objects
//getter and setter
}
class gemspartneractivity
{
private gems_partner part;
private gemsactivity act;
private boolean hold_transmission;
private boolean transmit_realtime;
//getter and setter
}


PS : please don't forget to give credits below if you found this answer useful :)

This should work for me - thanks.

James