JAXB: Annotations of field declared in superclass differ in subclasses

Question

I will try to explain the issue with an example:

Base:

public abstract class Base {
   protected Foo foo;
}

Derived1:

//@SomeXMLAnnotations
public class Derived1 extends Base {
   //Here i would like to define annotations for foo
   @XmlElements({
       @XmlElement(name = "foo1",   type = Foo1.class),
       @XmlElement(name = "foo2",   type = Foo2.class)
   })
   //@AnyAnnoations..
   //protected Foo foo;
}

Derived2:

//@SomeXMLAnnotations
public class Derived2 extends Base {
   //Here i would like to define annotations for foo too
   //But they will differ from the ones defined in Derived1
   @XmlElements({
       @XmlElement(name = "foo3", type = Foo3.class),
       @XmlElement(name = "foo4", type = Foo4.class)
   })
   //@AnyAnnoations..
   //protected Foo foo;
}

The @XmlElements annotation is just an example. It should work with any other annotation too.

I know I could shadow the superclass foo field but I dont think it's a proper way to solve this issue.

So is it possible in java (with JAXB) to override/add annotation of/to a field that is declared in a superclass?

Answer 1

"Ugly" solution:

//@SomeXMLAnnotations
public class Derived1 extends Base {

   //@AnyAnnoations..
   public Foo getFoo() { 
       return this.foo 
   }

   protected Foo setFoo(Foo foo) { 
       this.foo = foo; 
   }
}

Overriding/adding properties and annotating them seems to work. If getter or setter is never used somewhere it's pretty ugly though, because this has to happen in every subclass.