URGENT: Classloading issue: No class found even that the cla

[thuesler]

Hi all

I am still fighting around my classloading problems. Acutally I use JDom and Dom4j with Xerxes as parser... When I try to load some classes I get a class not found exception.

The following is the call Stack:
JXML Helper (myEAR) calls...

XPath (Jdom.jar contained in myEAR but uses the one from the Jboss Bootstrap (Jboss Dir\lib)) creates new Instance of..

JaxenXPath (contained in the jDom.jar) includes / uses some Sax stuff (SaxPathException) contained in Dom4j.jar

SaxPathException (contained in dom4j.jar which is in my ear) is attempted to be loaded but not found

Below the print of org.jboss.util.Debug.displayClassInfo (printed in the JXMLHelper => last class that I have under control):

14:27:22,777 INFO [STDOUT] Classloading information from JXMLHelper:
Debug Information for JXmlHelper class itself:

ch.argentis.base.xml.JXmlHelper(d7cf62).ClassLoader=org.jboss.mx.loading.UnifiedClassLoader3@1a517bd{ url=file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1
.24/server/tebs/tmp/deploy/tmp55706tebs-0.1-SNAPSHOT.ear ,addedOrder=24}
..org.jboss.mx.loading.UnifiedClassLoader3@1a517bd{ url=file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/server/tebs/tmp/deploy/tmp55706tebs-0.1-SNAPSH
OT.ear ,addedOrder=24}
..org.jboss.system.server.NoAnnotationURLClassLoader@e3b895
..sun.misc.Launcher$AppClassLoader@e80a59
....file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/bin/
....file:/C:/Entwicklungstools/abaXX/components36/lib/3rdparty/oracle9iR2.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/lib/tools.jar
....file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/bin/run.jar
..sun.misc.Launcher$ExtClassLoader@1ff5ea7
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/dnsns.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/ldapsec.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/localedata.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/sunjce_provider.jar
++++CodeSource: (file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/server/tebs/tmp/deploy/tmp55706tebs-0.1-SNAPSHOT.ear-contents/tebs-migration-0.1-SNAP
SHOT.jar <no certificates>)
Implemented Interfaces:
14:27:22,777 INFO [STDOUT] Debug Information for JDom class XPath:

org.jdom.xpath.XPath(14ad296).ClassLoader=org.jboss.system.server.NoAnnotationURLClassLoader@e3b895
..org.jboss.system.server.NoAnnotationURLClassLoader@e3b895
..sun.misc.Launcher$AppClassLoader@e80a59
....file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/bin/
....file:/C:/Entwicklungstools/abaXX/components36/lib/3rdparty/oracle9iR2.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/lib/tools.jar
....file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/bin/run.jar
..sun.misc.Launcher$ExtClassLoader@1ff5ea7
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/dnsns.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/ldapsec.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/localedata.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/sunjce_provider.jar
++++CodeSource: (file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/lib/jdom.jar <no certificates>)
Implemented Interfaces:
++interface java.io.Serializable(f62373)
++++ClassLoader: null
++++Null CodeSource
14:27:22,777 INFO [STDOUT] Debug Information for Dom4J class SAXPathException:

org.saxpath.SAXPathException(1399ae5).ClassLoader=org.jboss.mx.loading.UnifiedClassLoader3@1a517bd{ url=file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.2
4/server/tebs/tmp/deploy/tmp55706tebs-0.1-SNAPSHOT.ear ,addedOrder=24}
..org.jboss.mx.loading.UnifiedClassLoader3@1a517bd{ url=file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/server/tebs/tmp/deploy/tmp55706tebs-0.1-SNAPSH
OT.ear ,addedOrder=24}
..org.jboss.system.server.NoAnnotationURLClassLoader@e3b895
..sun.misc.Launcher$AppClassLoader@e80a59
....file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/bin/
....file:/C:/Entwicklungstools/abaXX/components36/lib/3rdparty/oracle9iR2.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/lib/tools.jar
....file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/bin/run.jar
..sun.misc.Launcher$ExtClassLoader@1ff5ea7
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/dnsns.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/ldapsec.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/localedata.jar
....file:/C:/Entwicklungstools/j2sdk_1.4.2_03/jre/lib/ext/sunjce_provider.jar
++++CodeSource: (file:/C:/Entwicklungstools/jboss-3.2.3_tomcat-4.1.24/server/tebs/tmp/deploy/tmp55706tebs-0.1-SNAPSHOT.ear-contents/dom4j-1.4.jar <no certi
ficates>)
Implemented Interfaces:

Actually when the code then runs through to the XPath and tries to load the SaxPathException I get the following stack trace:

14:27:22,793 ERROR [LogInterceptor] Unexpected Error:
java.lang.NoClassDefFoundError: org/saxpath/SAXPathException
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:141)
at org.jdom.xpath.XPath.newInstance(XPath.java:133)
at ch.argentis.base.xml.JXmlHelper.getValue(JXmlHelper.java:167)
at ch.argentis.base.xml.JXmlHelper.getTextOrNull(JXmlHelper.java:133)
at ch.argentis.base.util.Configuration.getTextOrNull(Configuration.java:158)
at ch.argentis.base.util.Configuration.getString(Configuration.java:168)
at ch.argentis.base.util.Configuration.init(Configuration.java:86)
at ch.argentis.base.util.Configuration.(Configuration.java:68)
at ch.argentis.base.util.Configuration.(Configuration.java:41)
at ch.argentis.base.util.logging.LoggerFactory.(LoggerFactory.java:43)
at ch.argentis.base.persistence.core.common.SystemStartupBean.(SystemStartupBean.java:48)
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:274)
at java.lang.Class.newInstance0(Class.java:308)
at java.lang.Class.newInstance(Class.java:261)
at org.jboss.ejb.Container.createBeanClassInstance(Container.java:469)
at org.jboss.ejb.plugins.AbstractInstancePool.get(AbstractInstancePool.java:168)
at org.jboss.ejb.plugins.StatelessSessionInstanceInterceptor.invoke(StatelessSessionInstanceInterceptor.java:58)
at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:84)
at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:297)
at org.jboss.ejb.plugins.TxInterceptorCMT.invoke(TxInterceptorCMT.java:128)
at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:118)
at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:191)
at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:122)
at org.jboss.ejb.StatelessSessionContainer.internalInvoke(StatelessSessionContainer.java:331)
at org.jboss.ejb.Container.invoke(Container.java:700)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.jboss.mx.capability.ReflectedMBeanDispatcher.invoke(ReflectedMBeanDispatcher.java:284)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:546)
at org.jboss.invocation.local.LocalInvoker.invoke(LocalInvoker.java:101)
at org.jboss.invocation.InvokerInterceptor.invoke(InvokerInterceptor.java:90)
at org.jboss.proxy.TransactionInterceptor.invoke(TransactionInterceptor.java:46)
at org.jboss.proxy.SecurityInterceptor.invoke(SecurityInterceptor.java:45)

For me it looks like jboss has some mess with the classloaders and doesn't loads the class from my ear but tries to load it using the Bootstrap classloader itself...

Any help is appreciated as no deployment is possible any more

Kind regards
tom

[adrian.brock]

< snip />

14:27:22,793 ERROR [LogInterceptor] Unexpected Error:
java.lang.NoClassDefFoundError: org/saxpath/SAXPathException
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:141)
at org.jdom.xpath.XPath.newInstance(XPath.java:133)
at ch.argentis.base.xml.JXmlHelper.getValue(JXmlHelper.java:167)

For me it looks like jboss has some mess with the classloaders and doesn't loads the class from my ear but tries to load it using the Bootstrap classloader itself...

Who has some mess?

Thread.currentThread().getContextClassLoader().loadClass() not Class.forName()

[thuesler]

Adrian

Thanks a lot for your fast reply. Acutally I relly did not recognize that is using Class.forName()...

This is an indepent library out of my control, that actually JBoss is also using.

Do I have any chance to influence the behaviour of Class.forName() in a way that it will use the right classloader'????? Actually I mean JBoss also uses this library and seems to come up correctly... Why that?

kind regards
t

[adrian.brock]

JBoss doesn't try to plugin user land classes.

Put your class in a jar inside $JBOSS_HOME/lib
then start jboss with

./run.sh -L myjar.jar

Or get the jdom project to fix it.

[thuesler]

Adrian

Thanks again... With the -L switch I got it running...

Cool end for a friday...

Nice weekend
-t

[chrisdutz]

Hmmm ... is there a way to use JDom and Xpath within Jboss without having to do the "-L"-parameter stuff? I need to use Xpath inside an application and I don't want to do any hacks to the command-line.

Chris

[vivkap01]

Hi
I have a similar problem. I am using JBoss 3.2.3 and JDOM b9. I get this error:
ROR [STDERR] java.lang.NoClassDefFoundError: org/saxpath/SAXPathException
2004-06-01 22:13:31,500 ERROR [STDERR] at java.lang.Class.forName0(Native Method)
2004-06-01 22:13:31,500 ERROR [STDERR] at java.lang.Class.forName(Class.java:141)
2004-06-01 22:13:31,500 ERROR [STDERR] at org.jdom.xpath.XPath.newInstance(XPath.java:126)
2004-06-01 22:13:31,500 ERROR [STDERR] at com.bitfone.server.commons.util.JDOMParser.getElement(JDOMParser.java:179)
2004-06-01 22:13:31,500 ERROR [STDERR] at com.bitfone.server.commons.util.JDOMParser.getElementText(JDOMParser.java:146)


It works fine on Tomcat/Weblogic and Orion but gives this error only on JBoss.
Is there a solution other than using the -L switch? Or is this a JDOM error and it is not going to work unless it is fixed in JDOM ?

--Viv

[chrisdutz]

I solved my problems by switching to dom4j ... I know this is a very unprofessional way, but I didn't have the time to figure out how to use XPath and dom4j is not used anywhere in jboss ;)

Give it a try, the changes are not too big
Chris

[juha]

Class.forName() is going to cause problems.

[starksm64]

dom4j is used by jboss-3.2.4

[wolfc]

Who has some mess?

Thread.currentThread().getContextClassLoader().loadClass() not Class.forName()

I disagree, when I do an import org.domain.SomeObject (and use it) it will be loaded by the currentClassLoader, not by the contextClassLoader. So in effect jdom uses saxpath as an import / hard depency. Nothing wrong with that.

IMHO the forest of UCLs is the problem. (or is that a flock? :-) )

Of one thing I'm sure: jBoss should not expose jdom.jar to deployed applications.

Don't get me wrong I like the UCL forest.
Ah I think I'm beginning to see the start of the tunnel:
- A.ear gets deployed
- B.ear wants to use interfaces
- either via same class loader to avoid class cast ex, or through marshalling which is slow
thus JBoss puts it all on one heap / loader repository.

The last part is not the way I preffer it.
What if:
- A.ear gets deployed
- B.ear gets deployed
both with hierarchical repositories which can access children.
Then A would load from (in order of priority) (very much simplified):
- server/test/deploy/A.ear/lib
- server/test/lib (parent)
- server/test/deploy/B.ear (siblings of parent)
- lib (parent)
- server/other/lib (siblings of parent)

This way jdom will get exposed but at a very late stage.

[starksm64]

If an ear is deployed with a heirarchical loader configuration no other deployment can load classes from it.