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JPA many-to-many with extra attribute

 
Greenhorn
Posts: 9
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Hi,

I have this tables:

Table: users

id integer
name varchar

Table: user_contacts

user_id integer
contact_id integer
active boolean

This is a self many-to-many relationship (user_id and contact_id is an user) with an extra attribute.

How I can map this with JPA?

With hibernate I do this:



Thank you!

Jair
 
author
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In Hibernate you were in-lining a composite object and defining a 1-m relationship to te contact object, with a m-1 back from the contact to the user. Similarly, in JPA you would define a contact entity and a 1-m relationship from user to contact and m-1 from contact to user. The only difference is that in JPA contact is a 1st class entity instead of a second class composite.
 
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