Your Hibernate association is not persisted?

Filed under: tech — Tags: , , — thomas11 @ 19:57

I spent a really frustrating day struggling with a weird bug in my app: some action would associate two entities via a javax.persistence.ManyToMany-mapped collection.  And this association would just be ignored by Hibernate, the link table/join table remained empty.  Finally, I found the solution in a post by Adrian Smith (and an update specifically for JPA in a comment by Sat Freak).  You saved my day!  I’m linking it here so that people may perhaps find it more easily.

The solution: do a flush(), then a merge(), then a commit().  Looks quite strange to me, and I can’t wrap my head around why that works and all my other approaches didn’t.  But work it does.

Create a free website or blog at