org.hibernate.PersistentObjectException: detached entity passed to persist

Question

I had successfully written my first master child example with hibernate. After few days I took it again and upgraded some libraries. No sure what did I do but I could never

Answer 1

I had the "same" problem because I was writting

@GeneratedValue(strategy = GenerationType.IDENTITY)

I deleted that line due that I do not need it at the moment, I was testing with objects and so. I think it is in your case

I do not have any controller and my API is not being accessed, it is only for testing (at the moment).