WildFly 12.0.0.Final JSF 2.3 & f:websocket - Class loader issue

Question

Trying to get an EJB to notify my XHTML JSF page when a document (row) has been inserted into a MongoDB collection.

Got JSF 2.3 working thanks to the answer to my earlier question:

However after adding the serverside code to my EJB and trying to deploy my EAR to WildFly 12.0.0.Final I get a java.lang.ClassNotFoundException for PushContext:

Caused by: java.lang.RuntimeException: WFLYSRV0177: Error getting reflective information for class com.notifywell.ejb.FoodsCosmeticsMedicinesEJB with ClassLoader ModuleClassLoader for Module "deployment.NOTiFYwell.ear.NOTiFYwellJAR.jar" from Service Module Loader

    at java.lang.Class.getDeclaredFields0(Native Method)
    at java.lang.Class.privateGetDeclaredFields(Class.java:2583)
    at java.lang.Class.getDeclaredFields(Class.java:1916)
    at org.jboss.as.server.deployment.reflect.ClassReflectionIndex.<init>(ClassReflectionIndex.java:72)
    at org.jboss.as.server.deployment.reflect.DeploymentReflectionIndex.getClassIndex(DeploymentReflectionIndex.java:70)
    ... 13 more
Caused by: java.lang.ClassNotFoundException: javax.faces.push.PushContext from [Module "deployment.NOTiFYwell.ear.NOTiFYwellJAR.jar" from Service Module Loader]
    at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:199)
    at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:412)
    at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:400)
    at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:116)
    ... 18 more

used in EJB:

@Inject
@Push
private PushContext push;

contained in:

jboss-jsf-api_2.3_spec-2.3.3.SP1.jar

This occurs when I add the @Inject to the @Push.

Any issues with CDI in WildFly 12 and/or JSF 2.3?

The ejb layer (backend) should not know anything about push (frontend). Use cdi events in the ejb) with observers in the frontend to communicate the two layers. See https://stackoverflow.com/questions/25947790/real-time-updates-from-database-using-jsf-java-ee — Kukeltje, Apr 16 '18 at 17:52
I was following BalusC's JSF 2.3+ example here: https://stackoverflow.com/questions/3787514/how-can-server-push-asynchronous-changes-to-a-html-page-created-by-jsf. — NOTiFY, Apr 16 '18 at 18:13
Correct, but If you look closely, you'll see the push being used in the frontend cdi bean (in the war) which also has an observes for events and the event is thrown in the stateless ejb. No 'push' is in the EJB. — Kukeltje, Apr 16 '18 at 18:29

score 8 · Accepted Answer · edited Jun 20 '20 at 09:12

used in EJB:
@Inject
@Push

You should never use frontend-targeted libraries in EJBs. This way your EJBs become tight coupled to the JSF frontend and totally unreusable for other frontends such as JAX-RS, JSP/Servlet, etc.

The @Push documentation even explicitly mentions to inject it in WAR side only.

You only need to keep in mind to explicitly instruct WildFly 12 to use standalone-ee8.xml when you intend to use JSF 2.3 on it. Also when used in the IDE. In Eclipse, when creating the server, you can specify it in the Configuration file entry of New Server wizard, which defaults to standalone.xml.

If you're still facing class loading trouble, then it can only mean that you have messed up the runtime classpath in other way. This can have more causes which are not visible in the information provided so far. For a starter like you who doesn't immediately mention the classpath configuration in a question about classpath trouble (and thus indicates ignorance about it), it's best to not mess around with the runtime classpath (or the "Build Path" and "Libraries" as called in the average IDE) until you grok it. Java EE provides by default already everything out the box, there's absolutely no need to adjust libraries in the project.

Leave everything as default, inject @Push in WAR instead of EJB and tell WildFly to run in EE8 mode and everything should go well.

WildFly 12.0.0.Final JSF 2.3 & f:websocket - Class loader issue

1 Answers1

See also:

See also:

See also: