You can't work with more than one entity group in a single transaction. This is a limitation of GAE, although other people have built distributed 2pc-style transactions on top of the datastore.
This should help: http://code.google.com/p/objectify-appengine/wiki/Concepts#Transactions Jeff On Wed, May 19, 2010 at 2:16 PM, laurent <bagno_laur...@hotmail.com> wrote: > i've searched for this error but don't find what it is. > > my code : > ObjectifyService.register(Lock.class); > ObjectifyService.register(Connection.class); > ObjectifyService.register(Assignment.class); > > if > (ObjectifyService.begin().query(Connection.class).countAll() == > 0) { > > Objectify obj = ObjectifyService.beginTransaction(); > obj.put(new Connection("DE PESSEMIER", "Johann", > "projet")); > obj.put(new Connection("AUCQUIERE", "Eric", "projet")); > > obj.put(new Lock(1l)); > > obj.getTxn().commit(); > } > > com.google.gwt.user.server.rpc.UnexpectedException: Service method > 'public abstract java.util.List > miro.shared.GreetingService.getConnections()' threw an unexpected > exception: java.lang.IllegalArgumentException: can't operate on > multiple entity groups in a single transaction. found both Element { > type: "Connection" > id: 5 > } > and Element { > type: "Connection" > id: 6 > } > > at > com.google.gwt.user.server.rpc.RPC.encodeResponseForFailure(RPC.java: > 378) > at > com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java: > 581) > at > com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java: > 188) > at > com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java: > 224) > at > com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java: > 62) > at javax.servlet.http.HttpServlet.service(HttpServlet.java:713) > at javax.servlet.http.HttpServlet.service(HttpServlet.java:806) > at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java: > 511) > at org.mortbay.jetty.servlet.ServletHandler > $CachedChain.doFilter(ServletHandler.java:1166) > at > com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java: > 51) > at org.mortbay.jetty.servlet.ServletHandler > $CachedChain.doFilter(ServletHandler.java:1157) > at > com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java: > 43) > at org.mortbay.jetty.servlet.ServletHandler > $CachedChain.doFilter(ServletHandler.java:1157) > at > com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java: > 122) > at org.mortbay.jetty.servlet.ServletHandler > $CachedChain.doFilter(ServletHandler.java:1157) > at > org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java: > 388) > at > org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java: > 216) > at > org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java: > 182) > at > org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java: > 765) > at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java: > 418) > at > com.google.apphosting.utils.jetty.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java: > 70) > at > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > 152) > at com.google.appengine.tools.development.JettyContainerService > $ApiProxyHandler.handle(JettyContainerService.java:349) > at > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > 152) > at org.mortbay.jetty.Server.handle(Server.java:326) > at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java: > 542) > at org.mortbay.jetty.HttpConnection > $RequestHandler.content(HttpConnection.java:938) > at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755) > at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218) > at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) > at > org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java: > 409) > at org.mortbay.thread.QueuedThreadPool > $PoolThread.run(QueuedThreadPool.java:582) > > Thanks for your request > > -- > 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-j...@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. > > -- 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-j...@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.
