GroupModel group = (GroupModel)iter.next(); group.clearThumbnails();
models[i].clearThumbnails();
    public void clearThumbnails()    {        thumbnailSet.clear();        for(Iterator iter = groupModels.iterator(); iter.hasNext();)        {            GroupModel group = (GroupModel)iter.next();            group.clearThumbnails();        }        updateModelListeners();    }