Please have a look at the following piece of codes: The ServiceLocator implementation: https://github.com/messo/KFC/blob/master/kfc-war/src/main/java/hu/sch/kfc/server/BeanLocator.java
<https://github.com/messo/KFC/blob/master/kfc-war/src/main/java/hu/sch/kfc/server/BeanLocator.java> EntityLocator: https://github.com/messo/KFC/blob/master/kfc-war/src/main/java/hu/sch/kfc/server/EntityLocator.java <https://github.com/messo/KFC/blob/master/kfc-war/src/main/java/hu/sch/kfc/server/EntityLocator.java>It's used for single entities. An example RequestContext: https://github.com/messo/KFC/blob/master/kfc-war/src/main/java/hu/sch/kfc/shared/service/GroupRequestContext.java <https://github.com/messo/KFC/blob/master/kfc-war/src/main/java/hu/sch/kfc/shared/service/GroupRequestContext.java>Note the locator = BeanLocator stuff And the implementation which is an EJB: https://github.com/messo/KFC/blob/master/kfc-ejb/src/main/java/hu/sch/kfc/ejb/GroupManager.java <https://github.com/messo/KFC/blob/master/kfc-ejb/src/main/java/hu/sch/kfc/ejb/GroupManager.java>It was working a several weeks ago with 2.2, I didn't checked with 2.3. 2011/5/17 andre.doelger <andre.doel...@freenet.de> > Hi, > > the example implementation is not really working. I've tried a > RequestFactory/EJB integration like this with GWT 2.3. > When findGroups() is called from a GWT client the EJB look-up via > BeanLocator is okay. But before GWT returns the objects to the client > it directly creates a instance of GroupManager and calls find() for > each returned object. The dependcy injection did not take place and > the EntityManager is null -> NullPointerexception. > > What I do not understand: > > 1. Why does the RequestFactory directly creates an instance of the > Locator and do not use the ServiceLocator? > 2. Why call find() for each entity that is returned in the List -> > Creates n+1 SQL calls > > Regards, > > André > > > On 2 Feb., 12:25, Bálint Kriván <bal...@krivan.info> wrote: > > Ok, I've found the problem: > > > > Using EJB bean for Locator implementation isn't good, because GWT > > instantiate it, so we have to make a EntityLocator, which lookups for the > > EJB and invoke the right methods. I hope this helps to the others! > > > > 2011/2/2 Bálint Kriván <bal...@krivan.info> > > > > > > > > > > > > > > > > > > > > > Hi! > > > > > Did anybody tried to use RequestFactory with EJB Beans using > > > Locator/ServiceLocator? > > > > > I'm having a little issue here. > > > > > My stateless session bean extends Locator<Group, Long>. For my > > > RequestContext I use a ServiceLocator which uses > InitialContext.doLookup(); > > > to lookup the EJB (I can't use @EJB because the ServiceLocator instance > > > isn't container-managed -- btw. is there any solution for this? lookup > looks > > > ugly). Everything looks fine, but in my Bean, the entityManager > instance is > > > null (I'm using @PersistenceContext annotation on it) when GWT wants to > > > invoke find(Class<?>, Long) method: here I use simple em.find(). It's > > > strange because invoking from a servlet, using @EJB, it works fine. > What am > > > I doing wrong? > > > > > I've created a gist for it:https://gist.github.com/807082 > > > > > So in this file: > https://gist.github.com/807082#file_group_manager.javaLine > > > #29, the em is null, but using this servlet: > > >https://gist.github.com/807082#file_test_servlet.javait works > perfectly. > > > > > Has anybody experience with this problem? I would like to use EJBs, > because > > > I would like to have JTA and Container-managed transactions. Thanks for > any > > > advice! > > > > > -- > > > Regards, > > > Bálint Kriván > > > > -- > > Üdv, > > Kriván Bálint > -- Üdv, Kriván Bálint -- You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To post to this group, send email to google-web-toolkit@googlegroups.com. To unsubscribe from this group, send email to google-web-toolkit+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-web-toolkit?hl=en.
