Meanwhile I tried this *java* code: PersistenceManagerFactory pmf = JDOHelper.getPersistenceManagerFactory( "transactions-optional" ); PersistenceManager pm = pmf.getPersistenceManager(); Antwort objectById = pm.getObjectById( Antwort.class, parameters.getLong( Constants.ID ) );
And this is my *jdocnfig.xml*: <?xml version="1.0" encoding="utf-8"?> <jdoconfig xmlns="http://java.sun.com/xml/ns/jdo/jdoconfig"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:noNamespaceSchemaLocation="http://java.sun.com/xml/ns/jdo/jdoconfig";> <persistence-manager-factory name="transactions-optional"> <property name="javax.jdo.PersistenceManagerFactoryClass" value="org.datanucleus.store.appengine.jdo.DatastoreJDOPersistenceManagerFactory"/> <property name="javax.jdo.option.ConnectionURL" value="appengine"/> <property name="javax.jdo.option.NontransactionalRead" value="true"/> <property name="javax.jdo.option.NontransactionalWrite" value="true"/> <property name="javax.jdo.option.RetainValues" value="true"/> <property name="datanucleus.appengine.autoCreateDatastoreTxns" value="true"/> </persistence-manager-factory> </jdoconfig> But I get the subsequent exception: javax.jdo.JDOFatalUserException: Application code attempted to create a PersistenceManagerFactory named transactions-optional, but one with this name already exists! Instances of PersistenceManagerFactory are extremely slow to create and it is usually not necessary to create one with a given name more than once. Instead, create a singleton and share it throughout your code. If you really do need to create a duplicate PersistenceManagerFactory (such as for a unittest suite), set the appengine.orm.disable.duplicate.pmf.exception system property to avoid this error. Can anybody help me out?! -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
