ensureRequiredPrimaryTypesLoaded throwing NullPointerException on first access under Jetty

Question

I am working on a "resource" controller using the latest Spring3 and JBoss Modeshape (pointing to a federated repository using the Filesystem connectors) to retrieve an asset.

When I access any webpage, using the controller, it returns most of the images then throws a NullPointerException in the "getNode" call at various other ones...

On my end, I am not doing anything special (my test cases work fine):

1. Create/configure the engine (only once)
2. Login and get a session
3. Try to find the node
4. Logout from the session

The code pretty much looks like:

session = createSession();
Node node = session.getNode(path);

After the first hit to the page (with errors), every hit after that works perfect and everything loads fine from then out.

I am following this link Heavy Concurrency: A better way to manage JCR Sessions for the session creation/management.

It appears as if I have multiple threads trying to configure the JcrNodeDefinition in Modeshape. If i mark the enureRequirePrimaryTypesLoaded() method as synchronized then I do not get the error ever.

Anyone have any experience/suggestions with using Modeshape, concurrency, and session management?

The stack trace is:

java.lang.NullPointerException at org.modeshape.jcr.JcrNodeDefinition.ensureRequiredPrimaryTypesLoaded(JcrNodeDefinition.java:114) at org.modeshape.jcr.JcrNodeDefinition.allowsChildWithType(JcrNodeDefinition.java:275) at org.modeshape.jcr.RepositoryNodeTypeManager.findChildNodeDefinition(RepositoryNodeTypeManager.java:1142) at org.modeshape.jcr.JcrNodeTypeManager.findChildNodeDefinition(JcrNodeTypeManager.java:433) at org.modeshape.jcr.SessionCache$JcrNodeOperations.materialize(SessionCache.java:2711) at org.modeshape.graph.session.GraphSession$Node.load(GraphSession.java:1755) at org.modeshape.graph.session.GraphSession$Node.getPayload(GraphSession.java:3030) at org.modeshape.jcr.AbstractJcrNode.getNode(AbstractJcrNode.java:950) at org.modeshape.jcr.AbstractJcrNode.getNode(AbstractJcrNode.java:96) at com.acme.beans.contents.FileNodeAdapter.(FileNodeAdapter.java:26) at com.acme.web.views.ResourceController.getStream(ResourceController.java:77) at com.acme.web.views.ResourceController.handleResource(ResourceController.java:46)

Answer 1

I'd recommend posting this on the ModeShape discussion forums and, in this case, logging an issue so the development team can evaluate it. Those are the best ways to directly communicate with ModeShape users and ask about ModeShape-specific problems or questions.