public XMLNode toNode(Groups object) throws Exception {
   XMLNode node = new XMLNode("groups");
   Attributes attrs = new Attributes(node);
   Object2XML mapper = Object2XML.getInstance();
   mapper.addNode(object.getGroups(), node, false, "list", "", "org.vietspider.model.Group");
   return node;
 }
 public XMLNode toNode(Category object) throws Exception {
   XMLNode node = new XMLNode("category");
   Attributes attrs = new Attributes(node);
   Object2XML mapper = Object2XML.getInstance();
   mapper.addNode(object.getCategoryName(), node, false, "category-name");
   mapper.addNode(object.getCategoryId(), node, false, "category-id");
   return node;
 }
 public XMLNode toNode(MetaRelations object) throws Exception {
   XMLNode node = new XMLNode("meta-relations");
   Attributes attrs = new Attributes(node);
   Object2XML mapper = Object2XML.getInstance();
   mapper.addNode(object.getMetaId(), node, false, "id");
   mapper.addNode(
       object.getMetaRelations(),
       node,
       false,
       "items",
       "item",
       "org.vietspider.bean.MetaRelation");
   return node;
 }