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Emulate @OneToMany association without adding a new Persistent Class

 
Carlos Conti
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Hi there,

is there anyway through annotations to create a list of arbitrary size to be bound to a persistent class, in such a way that it's not necessary to create an additional class?
Let me pose a short example:

Class A holds a list of "references" to Class B at running time.

Class B has no idea about A, and doesn't need to.

But somewhere I need to recall which references of B are bound to an instance of A.

Normally I would do this creating an intermediary persistent class, let's call it AB, where I would store a reference to both A and B, and would make AB persistent aswell. However if possible since I have to recall those values only at one very specific point of my application, I prefer to avoid creating the intermediary class and let's say store the ids Integer references of B in a persistent member of A, which at running time would be converted in a List with references to instances of class B.

Is that possible?

Manny thanks,

Carlos.
 
Carlos Conti
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Well,

in the meantime until someone figures out a better way, what I do is to virtually load/unload/edit a separate @Transient field of type ArrayList, where I update the references upon update of the string member that holds the list of Integer ids, separated by semicolons.

Regards,

Carlos.
 
Jayesh A Lalwani
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Can you post a code sample? It should be trivial to get the list of B from A if you are using JPA/Hibernate without using a relationship class or Transient. Maybe I am misunderstanding the problem. Posting a code sample would help
 
Arunsanjay Jayarathanam
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If I haven't misunderstood your problem, I think you are looking for a one to many unidirectional relationship without using an intermediate class as well without an intermediate table in the database?? Assuming that is right,here is an example that provides you a solution

JPA Wiki
 
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