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Adding to join table

tanil patel

Joined: Apr 10, 2013
Posts: 1

I have a TAG table and an ARTICLE table. The relationship in the ejb is set to many to many creating a join table automatically.

1) I get a string of tags and delimit them appropriately.
2) I then store each of the 'tokens' in an array.
3) Once getting these tokens, check each token and ensure it doesn't exist in the TAG table
3.1) If it does exist get that TAG object and store in the TAG_ARTICLE table
3.2) if it doesnt store the new tag in the TAG table aswell as the TAG_ARTICLE table.

Our problem is at 3.1; the tag is found but does not get added throwing an exception:
Error: javax.ejb.EJBException: javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: entities.Tag

3.2 however is working perfectly.

Thanks in advance,
Lucas Smith
Ranch Hand

Joined: Apr 20, 2009
Posts: 804

Please, provide the code of your entities.

It is sorta covered in the JavaRanch Style Guide.
subject: Adding to join table