Frontpage web hosting - APPENDIX A n MORE ADVANCED FEATURES 243 n
APPENDIX A n MORE ADVANCED FEATURES 243 n MORE ADVANCED FEATURES 243 Map names = new HashMap(); names.put(”user”,”sample.entity.User”); names.put(”advert”,”sample.entity.Advert”); names.put(”category”,”sample.entity.Category”); List entities = document.getRootElement().content(); Iterator eit = entities.iterator(); while(eit.hasNext()) { Node item = (Node)eit.next(); String entityName = (String)names.get(item.getName()); xmlSession.save(entityName,item); } session.getTransaction().commit(); session.close(); System.out.println(”Done.”); } } Unfortunately, the default value for the node attribute, if it is not explicitly applied to the class elements in the mapping files, is the short (unqualified) name of the class not the entity name, which defaults to the long (fully qualified) class name. Other Considerations When Using XML Entities The objects retrieved from Hibernate in the EntityMode.DOM4J session mode are Dom4J objects, but they are still Hibernate persistence entities. You can therefore manipulate these entities through the Dom4J API and persist these changes to the database without needing to access the entity as a POJO. Tools and APIs that process an XML document can therefore be applied to a Dom4J document extracted from Hibernate, and as long as it is still associated with the originating session, changes made to the document will be reflected in the database when the session is flushed or the transaction is committed. Hibernate and EJB 3 annotations do not provide support for the use of XML relational persistence. If you want to use this feature to import or export data for an annotated application, you will first need to generate appropriate XML-based mapping files from the annotated classes. Maps In addition to the default mode (POJO) and the XML mode (Dom4J) described previously, the Hibernate session can be accessed in one more way: as a map of name/value pairs. This mode is accessed by calling the getSession() method with a parameter of EntityMode.MAP (see Listing A-11).
Please visit our professional web hosting services to find out about cheap and reliable webhost service that will surely answer all your demands.