Hello,
I try to model the following structure:
A DomainModel has several Concepts as sons and
a Concept has several Categories as sons and
a Category may also have Categories as sons.
I modeled it like that:

public abstract class DomainModelElement<C extends DomainModelElement>
implements DomainModelTokens {
 protected Vector<C> children = new Vector<C>();
..
public class DomainModel extends DomainModelElement<Concept> {
..
public class Concept extends DomainModelElement<Category> {
..
public class Category extends DomainModelElement<Category> {  
..

So I pass the child type to the element, so I can use generic
implementations
of the methods for accessing the children. When I compile everything
works fine
until the compiler see the Category class. It says:

Bound mismatch: The type Category is not a valid substitute for the
bounded parameter <C extends DomainModelElement> of the type
DomainModelElement<C>    Category.java

although Category is a subclass of DomainModelElement<C>.
Can anybody help?

  Thanks beforehand,
          David Kensche