Factory method subclassing cayenne data objects

From: han..elinux.cl
Date: Sun Mar 01 2009 - 19:46:22 EST

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    Hi,

    I'm trying to implement a factory method pattern based on a cayenne data object.

    Say for example i have a class (cayenne based) called Artist, i want to make a subclass of Artist, say ExpertArtist that implements some specific behavior.

    Actually i have a big static Factory class that give me the all objects, i have a method like this:

            public static Artist getArtist(String id) {

                    if (id == null || id.equals(""))
                            return null;

                    DataContext context = DataContext.getThreadDataContext();

                    Artist object = (Artist) DataObjectUtils.objectForPK(
                                    context, Artist.class, Integer.parseInt(id));
                    return object;
            }

    Obviously i can declare ExpertArtist as an subclass of Artist.

    package xxx.xxx;

    public class EspertArtist extends Artist {
        public String getName() {
            return super.getName() + " i'am expert !!";
        }
    }

    I've tried to instantiate an ExpertArtist, just modifying the Factory method, with no results. I don't know how to bouild the parent class calling super or something...

    Obviously these are not the real classes, the actual classes are really big and this solution: just modifying the factory method is the best for me.

    Thanks
    Hans

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