Hi, there,

I'm a newbie of Hibernate, could you please give me some help over this problem?
I can't put too many words in the title so many it's not well explained...

My question is: I have to define an association like shown below:

| A |----------------- | B |
........(1..*)..........(1)

So I defined at the A side a "many-to-one" with not-null="true", and at the B side a "one-to-many" association:

<set name="myA" inverse="true">
<key column="B_ID"/>
<one-to-many class="A"/>
</set>

I tried to put a not-null="true" there too:
<one-to-many not-null="true" class="A"/>

but it's not allowed.

I spent quite some time searching for a solution but got nothing... Anyone could give me a hand?

Thanks a lot.

It doesn't make sense to put a not null on one-to-many since the one-to-many side is not usually the owner of the relation so if you only put it on the many-to-one side it is good enough.



Farzad-

Thanks Farzad. I got it.
But how can I then guarantee the "many" side to be "not null"?

I am wondering if you could use hibernate validation extension. It gives you enough facilities to make sure a collection has a minimum size.


Farzad-

Great!! Thanks a lot, I'll try it right now, :)