Hello everybody.

Ok, the question may seem completely stupid to ask but, after thinking a little about it, I find myself unable to precisely answer to it.

As I understand it, the @Entity annotation has to be added on classes that have to be persisted. But what happens when the classes I want to persist extend other classes or implement interfaces? Does each ancestor have to have the @Entity annotation added as well?

More specifically, if, when mapping Inheritance, I traverse an abstract class that does not have any property, do I still have to annotate it with @Entity or not?

If you know more about the details, could you also explain what technically happens when a class gets Annotated like this?

Thank you very much in advance,

Jérôme

Hi,
No you don't have to add @Entity to every class in the inheritence-tree. It is also not possible. Every class implicitly extends Object, which you can not annotate. ;-)

Only properties in the class, which is annotated as Entity are mapped.

Meaning that as soon as I have a property that I wish to see appearing in a table, I either have to map it with @Entity annotation (or @MappedSuperclass if I want to have some "templating", as I have just read).

But my question is still pending for abstract classes that do not hold any property.

Let's say that I have:
A (root - defines some properties)
B - C (middle abstract classes - no properties defined)
D (extends B and defines some properties)
E - F (idem as just above but for C).

Do I have to add the @Entity mapping for classes B and C? Why?

anyway, thank you for you response

Jérôme