Inability to use WebLogic native support without providing Tomcat, JBossWeb, etc. libs

[Alexander-Kiselyov]

Hello,

Following exception occurs during attempt to deploy WAR, which contains atmosphere-weblogic and uses org.atmosphere.weblogic.AtmosphereWebLogicServlet:

java.lang.NoClassDefFoundError: org/apache/catalina/CometProcessor
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
    at weblogic.utils.classloaders.GenericClassLoader.defineClass(GenericClassLoader.java:335)
    at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:288)
    at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:256)
    at weblogic.utils.classloaders.ChangeAwareClassLoader.findClass(ChangeAwareClassLoader.java:54)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
    at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:176)
    at weblogic.utils.classloaders.ChangeAwareClassLoader.loadClass(ChangeAwareClassLoader.java:35)
    at org.atmosphere.weblogic.AtmosphereWebLogicServlet.<clinit>(AtmosphereWebLogicServlet.java:38)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
&lt; s k i p p e d &gt;
    at weblogic.deploy.internal.targetserver.DeploymentManager.activateDeploymentList(DeploymentManager.java:1227)
    at weblogic.deploy.internal.targetserver.DeploymentManager.handleCommit(DeploymentManager.java:436)
    at weblogic.deploy.internal.targetserver.DeploymentServiceDispatcher.commit(DeploymentServiceDispatcher.java:164)
    at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer.doCommitCallback(DeploymentReceiverCallbackDeliverer.java:181)
    at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer.access$100(DeploymentReceiverCallbackDeliverer.java:12)
    at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer$2.run(DeploymentReceiverCallbackDeliverer.java:68)
    at weblogic.work.SelfTuningWorkManagerImpl$WorkAdapterImpl.run(SelfTuningWorkManagerImpl.java:516)
    at weblogic.work.ExecuteThread.execute(ExecuteThread.java:201)
    at weblogic.work.ExecuteThread.run(ExecuteThread.java:173)
java.lang.NoClassDefFoundError: org/apache/catalina/CometProcessor
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
    at weblogic.utils.classloaders.GenericClassLoader.defineClass(GenericClassLoader.java:335)
    at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:288)
    at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:256)
    at weblogic.utils.classloaders.ChangeAwareClassLoader.findClass(ChangeAwareClassLoader.java:54)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
    at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:176)
    at weblogic.utils.classloaders.ChangeAwareClassLoader.loadClass(ChangeAwareClassLoader.java:35)
    at org.atmosphere.weblogic.AtmosphereWebLogicServlet.<clinit>(AtmosphereWebLogicServlet.java:38)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
    at java.lang.Class.newInstance0(Class.java:355)
    at java.lang.Class.newInstance(Class.java:308)
    at weblogic.servlet.internal.WebComponentContributor.getNewInstance(WebComponentContributor.java:227)
    at weblogic.servlet.internal.WebComponentContributor.createServletInstance(WebComponentContributor.java:251)
    at weblogic.servlet.internal.StubSecurityHelper$ServletInitAction.run(StubSecurityHelper.java:255)
    at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
    at weblogic.security.service.SecurityManager.runAs(Unknown Source)
    at weblogic.servlet.internal.StubSecurityHelper.createServlet(StubSecurityHelper.java:64)
    at weblogic.servlet.internal.StubLifecycleHelper.createOneInstance(StubLifecycleHelper.java:58)
    at weblogic.servlet.internal.StubLifecycleHelper.<init>(StubLifecycleHelper.java:48)
    at weblogic.servlet.internal.ServletStubImpl.prepareServlet(ServletStubImpl.java:521)
    at weblogic.servlet.internal.WebAppServletContext.preloadServlet(WebAppServletContext.java:1896)
    at weblogic.servlet.internal.WebAppServletContext.loadServletsOnStartup(WebAppServletContext.java:1873)
    at weblogic.servlet.internal.WebAppServletContext.preloadResources(WebAppServletContext.java:1793)
    at weblogic.servlet.internal.WebAppServletContext.start(WebAppServletContext.java:3003)
    at weblogic.servlet.internal.WebAppModule.startContexts(WebAppModule.java:1375)
    at weblogic.servlet.internal.WebAppModule.start(WebAppModule.java:470)
    at weblogic.application.internal.flow.ModuleStateDriver$3.next(ModuleStateDriver.java:205)
&lt; s k i p p e d &gt;
    at weblogic.deploy.internal.targetserver.DeploymentManager.handleDeploymentCommit(DeploymentManager.java:820)
    at weblogic.deploy.internal.targetserver.DeploymentManager.activateDeploymentList(DeploymentManager.java:1227)
    at weblogic.deploy.internal.targetserver.DeploymentManager.handleCommit(DeploymentManager.java:436)
    at weblogic.deploy.internal.targetserver.DeploymentServiceDispatcher.commit(DeploymentServiceDispatcher.java:164)
    at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer.doCommitCallback(DeploymentReceiverCallbackDeliverer.java:181)
    at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer.access$100(DeploymentReceiverCallbackDeliverer.java:12)
    at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer$2.run(DeploymentReceiverCallbackDeliverer.java:68)
    at weblogic.work.SelfTuningWorkManagerImpl$WorkAdapterImpl.run(SelfTuningWorkManagerImpl.java:516)
    at weblogic.work.ExecuteThread.execute(ExecuteThread.java:201)
    at weblogic.work.ExecuteThread.run(ExecuteThread.java:173)

Problem is actually simple: line 38 of AtmosphereWebLogicServlet refers to AtmosphereServlet, which, in turn, implements org.apache.catalina.CometProcessor, org.jboss.servlet.http.HttpEventServlet:

protected static final Logger logger = LoggerFactory.getLogger(AtmosphereServlet.class);

According to the JLS, class literals will cause classloader to load class, and during this process NoClassDefFoundError can be thrown, exactly as in this case.
Not sure, whether it is an intended behaviour (that AtmosphereWebLogicServlet's logger is named equal to AtmosphereServlet's) or just a mistake.

Also, I've noted that Maven artifact atmosphere-runtime depends on atmosphere-compat-jbossweb, atmosphere-compat-tomcat, etc., so if one will assemble an app using Maven and won't exclude these artifacts - no problem will (obviously) occur. Is it actually possible to decouple runtime from container-specific artefacts?
"Structure of an Atmosphere's Application" states that: "You can remove some of the file if you don't need portability."

[jfarcand]

You need all the atmosphere-compat-xxx dependendencies to make it work. If you use Maven that should not be a problem?

[Alexander-Kiselyov]

Yes, with Maven it isn't a problem, as I said. But:

1. Documentation clearly says otherwise.
2. It seems illogical to force WebLogic-only (or Tomcat-only, etc.) users to drag irrelevant compatibility libraries.

[jfarcand]

Na just spotted the issue. I will fix the logging issue, and that should make it work.

[jfarcand]

Fixed. Try 1.0.10-SNAPSHOT (atmosphere-weblogic-1.0.10-20130130.203304-21.jar)

[Alexander-Kiselyov]

Thanks. Could you please tell, are there a lot of couplings between primary and compatibility libraries?

[jfarcand]

If you look at Atmosphere code, and to make it work with all Server, dependencies like this are required. Just exclude the atmosphere-compat-* from your pom.xml and Atmosphere will work. It is not a choice to do that, but to make sure application are portable.

[jfarcand]

No, small coupling and class are loaded by reflection, hence no issues unless a bug. I will also exclude the compat dependencies from atmosphere-weblogic so you should be fine. Give me 10 minutes

[Alexander-Kiselyov]

Thanks a lot, great responsiveness. I'm just researching the Atmosphere for potential use in my project and seems it's the right choice :)

[jfarcand]

Ok fixed. Let me know how it goes.