Ungraceful exit of JBossCacheManager Installation

[anil.saldhana]

In the TomcatDeployer codebase, the following section:

// Clustering
 if (metaData.getDistributable())
 {
 // Try to initate clustering, fallback to standard if no clustering is available
 try
 {
 AbstractJBossManager manager = null;
 String managerClassName = config.getManagerClass();
 Class managerClass = Thread.currentThread().getContextClassLoader().loadClass(managerClassName);
 manager = (AbstractJBossManager) managerClass.newInstance();

 if (manager instanceof JBossCacheManager)
 {
 // TODO either deprecate snapshot mode or move its config
 // into jboss-web.xml.
 String snapshotMode = config.getSnapshotMode();
 int snapshotInterval = config.getSnapshotInterval();
 JBossCacheManager jbcm = (JBossCacheManager) manager;
 jbcm.setSnapshotMode(snapshotMode);
 jbcm.setSnapshotInterval(snapshotInterval);
 }

 String name = "//" + ((hostName == null) ? "localhost" : hostName) + ctxPath;
 manager.init(name, metaData, config.isUseJK(), config.isUseLocalCache());

 // Don't assign the manager to the context until all config
 // is done, or else the manager will be started without the config
 server.setAttribute(objectName, new Attribute("manager", manager));

 log.debug("Enabled clustering support for ctxPath=" + ctxPath);
 }
 catch (ClusteringNotSupportedException e)
 {
 log.error("Failed to setup clustering, clustering disabled. Exception: " +e);
 }
 }

can exit abruptly without giving the web application an opportunity to be retrofitted with the valves to follow (Eg: SecurityAssociationValve). In fact, this situation can arise when the user has flagged the web app as distributable and is using the Apache Tomcat SSO valve and not the JBoss clustered valve. Ideally, if there are any errors, clustering should be disabled for the webapp (original intent of the author of this block).

An example of this issue is clearly seen in the following server log on cruisecontrol.
http://cruisecontrol.jboss.com/cc/artifacts/jboss-4.0-testsuite/20060419084946/build/output/jboss-4.0.4.GA/server/tomcat-sso/log/server.log

Please notice the following lines:

2006-04-19 10:17:02,716 WARN [org.jboss.system.ServiceController] Problem starting service jboss.web.deployment:id=1210098724,war=sso-form-auth2.war
java.lang.NoClassDefFoundError: org/jboss/web/tomcat/tc5/session/FieldBasedClusteredSession
 at java.lang.Class.getDeclaredConstructors0(Native Method)
 at java.lang.Class.privateGetDeclaredConstructors(Class.java:1618)
 at java.lang.Class.getConstructor0(Class.java:1930)
 at java.lang.Class.newInstance0(Class.java:278)
 at java.lang.Class.newInstance(Class.java:261)
 at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeployInternal(TomcatDeployer.java:318)
 at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeploy(TomcatDeployer.java:103)
 at org.jboss.web.AbstractWebDeployer.start(AbstractWebDeployer.java:371)

Basically, because of this error, the deployment of the webapp has stalled. And this setup does not use JBoss clustering. :-)

I am fixing this issue via a JIRA issue. This is FYI.

[anil.saldhana]

http://jira.jboss.com/jira/browse/JBAS-3152

The fix is this block. :-)

catch(Throwable t)
{
 log.error("Failed to setup clustering, clustering disabled. Exception: " +t);
}

[anil.saldhana]

Somebody from the Web Clustering team has to look into why the NoClassDefFoundError is happening during the JBossCacheManager installation.

[starksm64]

The FieldBasedClusteredSession has dependencies on aop/aspects classes that are not available. The NoClassDefFoundError is really for these, not the FieldBasedClusteredSession class.

[brian.stansberry]

I'll see why this is happening and fix it.

[anil.saldhana]

I built branch_4_0 and ran jboss with JDK4. That may be the real cause of this issue with the aop/aspects not being installed.

[starksm64]

At least I found one place where the underlying NoClassDefFoundError was being masked and fixed it because of this:
http://jira.jboss.com/jira/browse/JBAS-3153

22:58:43,092 ERROR [TomcatDeployer] Failed to setup clustering, clustering disabled. Exception:
java.lang.NoClassDefFoundError: org/jboss/aspects/patterns/observable/Observer
 at java.lang.ClassLoader.defineClass1(Native Method)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
 at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
 at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
 at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
 at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
 at java.security.AccessController.doPrivileged(Native Method)
 at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
 at org.jboss.mx.loading.RepositoryClassLoader.findClassLocally(RepositoryClassLoader.java:659)