Tutorial for make a non-generic type class from a generic type interface

Question

Hi there,
How can I make a non-generic type class from a generic type interface?
I appreciate if somebody let me know which site can help me.
Regards
Maurice

Answer 1

I have a generic interface with this signature
public interface IELO<K extends IMetadataKey>
and I have implemented a class from it
public class CmsELOImpl<K extends IMetadataKey> implements IELO<K>, Cloneable, Serializable
then I have to pass class of an instance CmsELOImpl to AbstractJcrDAO class constructor whit below signature
public abstract class AbstractJcrDAO<T> implements JcrDAO<T> {
public AbstractJcrDAO( Class<T> entityClass, Session session, Jcrom jcrom ) {
          this(entityClass, session, jcrom, new String[0]);
So I have made another class extended from AbstractJcrDAO. Below shows the code of this class and itd constructor
public class ELODaoImpl extends AbstractJcrDAO<CmsELOImpl<IMetadataKey>> {
     public ELODaoImpl( Session session, Jcrom jcrom ) {
     super(CmsELOImpl.class , session , jcrom, MIXIN_TYPES);
and as you see in its constructor I am calling the AbstractJcrDAO constructor by supper method
then I got this error on the line of super method
The constructor AbstractJcrDAO(class<CmsELOImpl>, session, Jcrom, String[]) is undefined.
as I know java generics are implemented using type erasure. This generics are only
in the java source file and not in the class files. The generics are only used by the compiler and
they are erased from the class files. This is done to make generics compatible with (old) non generics java code.
As a result the class object of AbstractJcrDAO<CmsELOImpl<IMetadataKey>>
is AbstractJcrDAO.class. The <CmsELOImpl<IMetadataKey>> information is
not available in the class file. As far as I understand it, I am looking a way
to pass <CmsELOImpl<IMetadataKey>>, if it is possible at all.
Maurice