[seam-issues] [JBoss JIRA] (JBSEAM-3848) Seam fails to create and inject components when multiple ajax-requests are fired from a commandLink or commandButton, using ajax4jsf.

Seam fails to create and inject components when multiple ajax-requests are fired from a commandLink or commandButton, using ajax4jsf. ------------------------------------------------------------------------------------------------------------------------------------- Key: JBSEAM-3848 URL: https://issues.jboss.org/browse/JBSEAM-3848 Project: Seam 2 Issue Type: Bug Components: Core Affects Versions: 2.0.0.BETA1 Environment: windows vista / rhel4 sun jdk5, jdk6 latest versions jboss as 4.2.2 and 4.2.3 firefox2 and 3, ie 6 and 7. Reporter: etirk etirk Assignee: Marek Novotny Labels: a4j, ajax, core, jsf, seam Fix For: 2.3.0.BETA1 Original Estimate: 2 days Remaining Estimate: 2 days Seam fails to create and inject components when multiple ajax-requests are fired from a commandLink or commandButton, using ajax4jsf. Replication found using seam-booking in examples, trunk as of 081216. Rewrite the find-method in the HotelSearchAction-class, in the seam booking example application. It should look like this. public void find() { page = 0; queryHotels(); try { Thread.sleep(1000 * 5); } catch (InterruptedException ignore) { } } Now, start the application, register a user and enter main.html. Click multiple times on the search hotel button. Depending upon how fast your computer is, you might need to do more than a double-click. Sometimes you may need to klick fast up to 5-8 times. But it will occur. You will end up with an exception that says: Caused by javax.servlet.ServletException with message: javax.el.ELException: /main.xhtml @74,130 rendered=#{hotelSearch.nextPageAvailable}: Error reading nextPageAvailable on type org.javassist.tmp.java.lang.Object_$$_javassist_4 Which in turn comes from a synchronization problem. Caused by org.jboss.seam.core.LockTimeoutException with message: could not acquire lock on @Synchronized component: hotelSearch This is in a way funny, since the hotelSearch-component is not annotated with synchronized. Anyway, our application does not throw an exception like this, but we to have tried synchronizing our involved components, with no luck. Our exception is mostly this Caused by javax.servlet.ServletException with message: javax.el.ELException: /layout/template.xhtml @18,59 rendered=#{authenticator.inSpecialMode}: Error reading inSpecialMode on type se.session.Authenticator_$$_javassist_4 Which in turn comes from the failed injections Caused by org.jboss.seam.RequiredException with message: @In attribute requires non-null value: authenticator.entityManager This problem occurs all over the application, always when an ajax request is double-clicked and seam tries to recreate seam components and runs out of time. In 99% of the case it is the first read property of our authenticator-component that fails, and most often it is that seam cannot create a entityManager to inject, and the system fails due to that the annotation is set to only inject, without create. Removing the entityManager from the component will only result in that seam cannot inject another component instead, until you have no injections left in authenticator, and it still fails! Similar behaviour has been noticed using non-ajax calls, using standard h:commandButton/Link. This is however much more rare.