Classloader in weblogic12c

I develop a spring+hibernate+struts web application and need to deploy it from a folder to weblogic12c.
However, after deployment, in Classloader Analysis Tool, 2 jars: WEB-INF/lib/hibernate-core-3.3.2.GA.jar, WEB-INF/lib/freemarker-2.3.15.jar show: The filtering classloader acts as a barrier between the application classloaders and the system classloaders. By configuring the filtering classloader correctly, the application can choose to load certain classes locally rather than from the system classpath.
Below is my weblogic-application.xml
<?xml version="1.0" encoding="UTF-8"?>
<weblogic-application xmlns="http://xmlns.oracle.com/weblogic/weblogic-application"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.oracle.com/weblogic/weblogic-application http://xmlns.oracle.com/weblogic/weblogic-application/1.4/weblogic-application.xsd">
     <application-param>
          <param-name>webapp.encoding.default</param-name>
          <param-value>UTF-8</param-value>
     </application-param>
     <prefer-application-packages>
          <package-name>javax.jws.*</package-name>
     </prefer-application-packages>
</weblogic-application>
What should I do next?
Thanks

Have a look at
http://www.onjava.com/pub/a/onjava/2001/07/25/ejb.html
Instantiating objects of a same class in different subunits will not cause errors, but it is true that, according to the classloading policy (configurable in application server), the behaviors of creational mecanisms such as singleton for example, can vary.
Bruno
http://www.practicalsoftwarearchitect.com

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How to enable web-app "parent-last" classloading in WLS 10.3?

Hello,
We are having some issues when using Groovy to execute ant tasks in a webapp. They are due to the classloading order in WLS.
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In Websphere you can set a checkbox for it in the console.
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Try either a filtering classloader as described here:
http://edocs.bea.com/wls/docs103/programming/classloading.html#wp1097187
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http://edocs.bea.com/wls/docs103/programming/classloading.html#wp1082452

Classloader Again

Sorry to bring up the classloader questions again and again. I am a bit confused by the language used in the documentation when it says things like each application has its own universe etc. And also, the following statement in the docs,
"The exception is the Web Classloader, which follows the delegation model in the Servlet specification. The Web Classloader looks in the local classloader before delegating to its parent. You can make the Web Classloader delegate to its parent first by setting delegate="true" in the class-loader element of the sun-web.xml file. For details, see the Developer's Guide to Web Applications."
I wanted to see if some one could answer the following. (These are very easy for me to test. But, at this point I have a very "rich" system classpath that includes a lot of classes/jars etc. Makes it harder to see a clear picture. And I want to see if what I am observing the correct behavior))
I have a com.xyz.myClass packaged in utils.jar. I also have a test servlet and jsp page. The test servlet makes a call to com.xyz.myClass
A) If I individually deploy my test servlet/jsp as a .WAR, where should I place utils.jar?
(If I had utils.jar in the system classpath, is the WAR supposed to see it?)
B) What if the a

I have a com.xyz.myClass packaged in utils.jar. I also have > a test servlet and jsp page. The test servlet makes a call to > com.xyz.myClass
A) If I individually deploy my test servlet/jsp as a .WAR,
where should I place utils.jar?You can place it in any one of a number of locations:
- within the WAR under WEB-INF/lib/. This location would be the most conventional, self-contained approach.
- under $INSTANCE_ROOT/lib/. This location would mean that the same "version" the library would be shared by all apps (assuming that the other apps did not include their own copy).
- under classpath-suffix setting for the instance. Similar to using $INSTANCE_ROOT/lib/, but you have to specify the JAR file name explicitly.
(If I had utils.jar in the system classpath, is the WAR
supposed to see it?)Yes.
B) What if the above .WAR was part of a larger .EAR and I > deploy the .EAR instead of the .WAR? (Should utils.jar
be in system class path or the web-inf/lib of the .WAR ?)Either.
C) What if the .EAR above also had a few EJBs that
accessed com.xyx.myClass ?- Self-contained approach would be to package the JAR file in the EAR and use the manifest classpath approach to denote its location for both the EJB JAR module and the WAR module.
- Alternatively, you could either place the library either under $INSTANCE_ROOT/lib/ or specify the library in the classpath-suffix setting in the instance configuration.
A good example of when it makes sense for the web classloader to look in the local classloader before delegating upward to the system classloader is the case in which your web application depends on a particular JAXP compatible XML parser that is different from that which is being used by the application server infrastructure. In this case, you would want the XML parser embedded in your web app or EAR to take precedence over the other XML parser packaged in the system classpath for use by the app server.
Chris

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Hi ALL,
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The native non-main (not the thread that initializes the JVM) threads would not be able to find any user-define class.
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I really appreciate it if anyone can provide any help/suggestion.
Regards,
- Triet

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public:
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Hi all,
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application.ear
|--> APP-INF
| |--> classes
| |--> lib (all jar dependencies go here, including the WAR dependencies, EJB module dependencies)
|-->META_INF
| |--> application.xml
| |--> data-sources.xml
| |--> MANIFEST.MF
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| |--> weblogic-application.xml
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|--> myEjbModule1.jar
|--> myEjbModule2.jar
|--> myEjbModule3.jar
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When deploying WITH jboss-seam-debug.jar, the application does not appear, but ONLY the debug page with the following exception (stacktrace at the end):
Exception during request processing:
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Edited by: user6410241 on Mar 24, 2010 8:14 AM
Edited by: user6410241 on Mar 24, 2010 8:26 AM

The problem was the name of the Seam EJB module. Changing the jar to jboss-seam.jar, everything worked. This issue does not appear on JBoss 4.2.3.GA, where I also tested.
Edited by: deadlock_gr on Jun 10, 2010 9:55 AM
Edited by: deadlock_gr on Jun 10, 2010 9:56 AM

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URL urls[] = new URL[] { new File(".").toURL() };
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Hi,
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}This is the test program I've created. It loads a class from the Apache log4j jar file, and deletes the file when the class is loaded:import java.io.File;
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NOTE: Posted over in Serialization forum as more appropriate there, sorry for the crosspost but didn't notice that forum at first. Please direct any replies there.
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I've managed to work around it for now by setting the contextClassLoader to the correct one before calling readObject() in XMLDecoder and then reverting it back immediately after, but this feels like somewhat of a hack to me.
I would've expected it to have been properly handled when passing the ClassLoader to XMLDecoder rather than like it is.
Anyone know if this is intended behaviour or a bug? and if the former is there any recommended way to deal with this other than the one I'm currently using.
NOTE: Posted over in Serialization forum as more appropriate there, sorry for the crosspost but didn't notice that forum at first. Please direct any replies there.
Message was edited by:
djb61
NOTE: Reposting to Serialization

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Problem with classloader (for shared-lib's) on oc4j 10.0.3.4 under jdk 1.5

I have a project that runs great on oc4j 10.0.3.4 under jdk 1.6. (everything worked great)
I recently tried to run it under jdk 1.5 and i've run into a little problem with the shared-lib's:
The classloader's debug file reports the following: (i have translated some of it)
Class error: oracle.classloader.util.AnnotatedNoClassDefFoundError:
     Missing class: javax.xml.bind.JAXBContext
Dependant class: nl.comp.util.XmlUtil
     Classloader: comp:0.1
     Code-source: /C:/programs/oc4j/j2ee/home/shared-lib/comp/0.1/comp.jar
     Configuration: <code-source> in /c:/programs/oc4j/j2ee/home/config/server.xml
The missing class is available from the following location:
     1. Code-source: /C:/programs/oc4j/lib/xml.jar (from <code-source> (ignore manifest Class-Path) in META-INF/boot.xml in C:\programs\oc4j\j2ee\home\oc4j.jar)
This code-source is available from classloader oracle.xml:10.1.0_2
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So the classloader knows where to find the necessary lib, but it isn't loading it? If i run the exact same code (with same descriptors and everything) under jdk 1.6, it works, under 1.5 i get the above error.
What is different on the class loader level between the two jdk versions that might affect the program in such a way?
Need i update a descriptor or do something else?

Jack,
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1. Try unsetting your "ClassPath" variable. Open a "command" window and type the following:
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Good Luck,
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Hi,
I am new to weblogic. I am encountering an error on trying to run the 'servicegen' command from my ant build scripts, on weblogic 9.2.
Please find the build.xml snapshot, and the stack trace given below.
Please help me out with this.
Points to be noted are:-
1) The ejb-jar.xml specifies the bean class, which is very much present in the classpath. The ejb-jar.xml is generated by xdoclet. Snapshot is given below:-
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN" "http://java.sun.com/dtd/ejb-jar_2_0.dtd">
<ejb-jar >
<description><![CDATA[No Description.]]></description>
<display-name>Generated by XDoclet</display-name>
<enterprise-beans>

<session >
<description><![CDATA[NorthBound Interface]]></description>
<ejb-name>ArcorNBIService</ejb-name>
<home>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceHome</home>
<remote>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIService</remote>
<local-home>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceLocalHome</local-home>
<local>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceLocal</local>
<ejb-class>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceBean</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
</session>
</enterprise-beans>
</ejb-jar>
2) When I replace the "ejbJar" attribute in the 'service' command with "javaClassComponents" attribute, I am able to run the servicegen command successfully. Not sure why the ejbJar is creating problems.
3) Build.xml snapshot:-
     <target name="gen-webservice" depends="init">
          <copy todir="${work.dir}" file="${export.dir}/lib/arcor-il-service-ejb.jar"/>
          <autotype javatypes="${javatypes}" targetNamespace="${targetNamespace}" destDir="${work.dir}/classes" keepGenerated="${keepGenerated}" classpathref="webservice.client.classpath"/>
          <autotype javaComponents="com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIService" targetNamespace="com.alcatel.hdm.service.nbi.dto.holders" destDir="${work.dir}/classes" keepGenerated="true" classpathref="webservice.client.classpath"/>
          <servicegen destEar="${earfile}" warName="${warname}" contextURI="${contextURI}" keepGenerated="${keepGenerated}" classpathref="webservice.client.classpath">
               <service ejbJar="${ejbLocation}" targetNamespace="${targetNamespace}" serviceName="${serviceName}" serviceURI="/${serviceName}" generateTypes="false" expandMethods="${expandMethods}" ignoreAuthHeader="false" protocol="https" style="rpc" useSOAP12="${useSOAP12}" typeMappingFile="${work.dir}/classes/types.xml">
                    <security enablePasswordAuth="true"/>
               </service>
          </servicegen>
     </target>
4) Exception stacktrace:-
--- Nested Exception ---
java.lang.AssertionError: java.io.IOException
at weblogic.descriptor.DescriptorManager$DefaultMarshallerFactorySingleton.<clinit>(DescriptorManager.java:42)
at weblogic.descriptor.DescriptorManager.getDefaultMF(DescriptorManager.java:116)
at weblogic.descriptor.DescriptorManager.getMarshallerFactory(DescriptorManager.java:125)
at weblogic.descriptor.DescriptorManager.getDescriptorFactory(DescriptorManager.java:153)
at weblogic.descriptor.DescriptorManager.createDescriptor(DescriptorManager.java:277)
at weblogic.descriptor.DescriptorManager.createDescriptor(DescriptorManager.java:248)
at weblogic.descriptor.DescriptorManager.createDescriptor(DescriptorManager.java:309)
at weblogic.descriptor.EditableDescriptorManager.createDescriptor(EditableDescriptorManager.java:99)
at weblogic.application.descriptor.AbstractDescriptorLoader.createDescriptor(AbstractDescriptorLoader.java:344)
at weblogic.application.descriptor.CachingDescriptorLoader.createDescriptor(CachingDescriptorLoader.java:188)
at weblogic.application.descriptor.AbstractDescriptorLoader.createDescriptor(AbstractDescriptorLoader.java:328)
at weblogic.application.descriptor.AbstractDescriptorLoader.getDescriptor(AbstractDescriptorLoader.java:237)
at weblogic.application.descriptor.AbstractDescriptorLoader.getRootDescriptorBean(AbstractDescriptorLoader.java:217)
at weblogic.ejb.spi.EjbJarDescriptor.getEjbJarBean(EjbJarDescriptor.java:141)
at weblogic.ejb.spi.EjbJarDescriptor.getEditableEjbJarBean(EjbJarDescriptor.java:182)
at weblogic.ejb.container.dd.xml.DDUtils.processEjbJarXMLWithSchema(DDUtils.java:519)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:182)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:126)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:154)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:147)
at weblogic.ejb.spi.DDUtils.createDescriptorFromJarFile(DDUtils.java:30)
at weblogic.webservice.dd.EJBJarIntrospector.<init>(EJBJarIntrospector.java:52)
at weblogic.ant.taskdefs.webservices.autotype.EJBAutoTyper.<init>(EJBAutoTyper.java:68)
at weblogic.ant.taskdefs.webservices.servicegen.ServiceGenTask.runAutoTyper(ServiceGenTask.java:339)
at weblogic.ant.taskdefs.webservices.servicegen.ServiceGenTask.generateService(ServiceGenTask.java:313)
at weblogic.ant.taskdefs.webservices.servicegen.ServiceGenTask.execute(ServiceGenTask.java:181)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:275)
at org.apache.tools.ant.Task.perform(Task.java:364)
at org.apache.tools.ant.Target.execute(Target.java:341)
at org.apache.tools.ant.Target.performTasks(Target.java:369)
at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1216)
at org.apache.tools.ant.Project.executeTarget(Project.java:1185)
at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:40)
at org.apache.tools.ant.Project.executeTargets(Project.java:1068)
at org.apache.tools.ant.Main.runBuild(Main.java:668)
at org.apache.tools.ant.Main.startAnt(Main.java:187)
at org.apache.tools.ant.launch.Launcher.run(Launcher.java:246)
at org.apache.tools.ant.launch.Launcher.main(Launcher.java:67)
Caused by: java.io.IOException
at weblogic.descriptor.internal.MarshallerFactory.<init>(MarshallerFactory.java:50)
at weblogic.descriptor.DescriptorManager$DefaultMarshallerFactorySingleton.<clinit>(DescriptorManager.java:40)
... 37 more
Caused by: com.bea.xml.XmlException: unable to load type library from classloader weblogic.utils.classloaders.ClasspathClassLoader@1cc0a7f f
inder: weblogic.utils.classloaders.CodeGenClassFinder@c52200 annotation:
at com.bea.staxb.runtime.internal.BindingContextFactoryImpl.createBindingContext(BindingContextFactoryImpl.java:50)
at weblogic.descriptor.internal.MarshallerFactory.<init>(MarshallerFactory.java:48)
... 38 more
Total time: 5 seconds

Hi,
I am new to weblogic. I am encountering an error on trying to run the 'servicegen' command from my ant build scripts, on weblogic 9.2.
Please find the build.xml snapshot, and the stack trace given below.
Please help me out with this.
Points to be noted are:-
1) The ejb-jar.xml specifies the bean class, which is very much present in the classpath. The ejb-jar.xml is generated by xdoclet. Snapshot is given below:-
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN" "http://java.sun.com/dtd/ejb-jar_2_0.dtd">
<ejb-jar >
<description><![CDATA[No Description.]]></description>
<display-name>Generated by XDoclet</display-name>
<enterprise-beans>

<session >
<description><![CDATA[NorthBound Interface]]></description>
<ejb-name>ArcorNBIService</ejb-name>
<home>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceHome</home>
<remote>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIService</remote>
<local-home>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceLocalHome</local-home>
<local>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceLocal</local>
<ejb-class>com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIServiceBean</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
</session>
</enterprise-beans>
</ejb-jar>
2) When I replace the "ejbJar" attribute in the 'service' command with "javaClassComponents" attribute, I am able to run the servicegen command successfully. Not sure why the ejbJar is creating problems.
3) Build.xml snapshot:-
     <target name="gen-webservice" depends="init">
          <copy todir="${work.dir}" file="${export.dir}/lib/arcor-il-service-ejb.jar"/>
          <autotype javatypes="${javatypes}" targetNamespace="${targetNamespace}" destDir="${work.dir}/classes" keepGenerated="${keepGenerated}" classpathref="webservice.client.classpath"/>
          <autotype javaComponents="com.alcatel.hdm.arcoril.webservice.ejb.ArcorNBIService" targetNamespace="com.alcatel.hdm.service.nbi.dto.holders" destDir="${work.dir}/classes" keepGenerated="true" classpathref="webservice.client.classpath"/>
          <servicegen destEar="${earfile}" warName="${warname}" contextURI="${contextURI}" keepGenerated="${keepGenerated}" classpathref="webservice.client.classpath">
               <service ejbJar="${ejbLocation}" targetNamespace="${targetNamespace}" serviceName="${serviceName}" serviceURI="/${serviceName}" generateTypes="false" expandMethods="${expandMethods}" ignoreAuthHeader="false" protocol="https" style="rpc" useSOAP12="${useSOAP12}" typeMappingFile="${work.dir}/classes/types.xml">
                    <security enablePasswordAuth="true"/>
               </service>
          </servicegen>
     </target>
4) Exception stacktrace:-
--- Nested Exception ---
java.lang.AssertionError: java.io.IOException
at weblogic.descriptor.DescriptorManager$DefaultMarshallerFactorySingleton.<clinit>(DescriptorManager.java:42)
at weblogic.descriptor.DescriptorManager.getDefaultMF(DescriptorManager.java:116)
at weblogic.descriptor.DescriptorManager.getMarshallerFactory(DescriptorManager.java:125)
at weblogic.descriptor.DescriptorManager.getDescriptorFactory(DescriptorManager.java:153)
at weblogic.descriptor.DescriptorManager.createDescriptor(DescriptorManager.java:277)
at weblogic.descriptor.DescriptorManager.createDescriptor(DescriptorManager.java:248)
at weblogic.descriptor.DescriptorManager.createDescriptor(DescriptorManager.java:309)
at weblogic.descriptor.EditableDescriptorManager.createDescriptor(EditableDescriptorManager.java:99)
at weblogic.application.descriptor.AbstractDescriptorLoader.createDescriptor(AbstractDescriptorLoader.java:344)
at weblogic.application.descriptor.CachingDescriptorLoader.createDescriptor(CachingDescriptorLoader.java:188)
at weblogic.application.descriptor.AbstractDescriptorLoader.createDescriptor(AbstractDescriptorLoader.java:328)
at weblogic.application.descriptor.AbstractDescriptorLoader.getDescriptor(AbstractDescriptorLoader.java:237)
at weblogic.application.descriptor.AbstractDescriptorLoader.getRootDescriptorBean(AbstractDescriptorLoader.java:217)
at weblogic.ejb.spi.EjbJarDescriptor.getEjbJarBean(EjbJarDescriptor.java:141)
at weblogic.ejb.spi.EjbJarDescriptor.getEditableEjbJarBean(EjbJarDescriptor.java:182)
at weblogic.ejb.container.dd.xml.DDUtils.processEjbJarXMLWithSchema(DDUtils.java:519)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:182)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:126)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:154)
at weblogic.ejb.container.dd.xml.DDUtils.createDescriptorFromJarFile(DDUtils.java:147)
at weblogic.ejb.spi.DDUtils.createDescriptorFromJarFile(DDUtils.java:30)
at weblogic.webservice.dd.EJBJarIntrospector.<init>(EJBJarIntrospector.java:52)
at weblogic.ant.taskdefs.webservices.autotype.EJBAutoTyper.<init>(EJBAutoTyper.java:68)
at weblogic.ant.taskdefs.webservices.servicegen.ServiceGenTask.runAutoTyper(ServiceGenTask.java:339)
at weblogic.ant.taskdefs.webservices.servicegen.ServiceGenTask.generateService(ServiceGenTask.java:313)
at weblogic.ant.taskdefs.webservices.servicegen.ServiceGenTask.execute(ServiceGenTask.java:181)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:275)
at org.apache.tools.ant.Task.perform(Task.java:364)
at org.apache.tools.ant.Target.execute(Target.java:341)
at org.apache.tools.ant.Target.performTasks(Target.java:369)
at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1216)
at org.apache.tools.ant.Project.executeTarget(Project.java:1185)
at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:40)
at org.apache.tools.ant.Project.executeTargets(Project.java:1068)
at org.apache.tools.ant.Main.runBuild(Main.java:668)
at org.apache.tools.ant.Main.startAnt(Main.java:187)
at org.apache.tools.ant.launch.Launcher.run(Launcher.java:246)
at org.apache.tools.ant.launch.Launcher.main(Launcher.java:67)
Caused by: java.io.IOException
at weblogic.descriptor.internal.MarshallerFactory.<init>(MarshallerFactory.java:50)
at weblogic.descriptor.DescriptorManager$DefaultMarshallerFactorySingleton.<clinit>(DescriptorManager.java:40)
... 37 more
Caused by: com.bea.xml.XmlException: unable to load type library from classloader weblogic.utils.classloaders.ClasspathClassLoader@1cc0a7f f
inder: weblogic.utils.classloaders.CodeGenClassFinder@c52200 annotation:
at com.bea.staxb.runtime.internal.BindingContextFactoryImpl.createBindingContext(BindingContextFactoryImpl.java:50)
at weblogic.descriptor.internal.MarshallerFactory.<init>(MarshallerFactory.java:48)
... 38 more
Total time: 5 seconds

HOT Redeployment of EAR fails with Classloader error

App Server: WLS 10.3
OS: Solaris 9
I have installed WLS installed with a domain, admin and a managed server. Everything is working fine.
I have WAR and EAR deployed successfully on the Managed Server.
HOT deployment of WAR files works perfectly fine.
There is this EAR "IIA.ear" with @ 8 WAR files and 1 jar "Manager.jar". The EAR has been deployed in the "nostage" mode.
I do not have any separate "Deployment" plan.
In order to "redeploy" the EAR I go to the Admin console >> Deployments >> Select the EAR >> update >> Source Path remains the same >> Finish
I get the following error :
+#####################+
weblogic.application.CannotRedeployException: Module 'Manager.jar' has the same ClassLoader as the Application 'IIA'. Consider redeploying the entire application.
Update operation failed - no deployments changed.
+#####################+
The log files shows below error
+#####################+
+<Sep 15, 2009 9:18:52 AM MEST> <Error> <Deployer> <BEA-149265> <Failure occurred in the execution of deployment request with+
ID '1252999132033' for task '8'. Error is: 'weblogic.application.CannotRedeployException: Module 'Manager.jar' has the
same ClassLoader as the Application 'IIA'. Consider redeploying the entire application.'
weblogic.application.CannotRedeployException: Module 'Manager.jar' has the same ClassLoader as the Application 'IIA'. Consider redeploying the entire application.
at weblogic.application.internal.AppClassLoaderManagerImpl.updatePartialDeploySet(AppClassLoaderManagerImpl.java:299)
at weblogic.application.internal.flow.TailModuleRedeployFlow.validateClassLoaderStructure(TailModuleRedeployFlow.java
+:135)+
at weblogic.application.internal.flow.TailModuleRedeployFlow.validateRedeploy(TailModuleRedeployFlow.java:97)
at weblogic.application.internal.BaseDeployment$ValidateRedeployStateChange.next(BaseDeployment.java:801)
at weblogic.application.utils.StateMachineDriver.nextState(StateMachineDriver.java:37)
Truncated. see log file for complete stacktrace
+>+
+#####################+
does WLS 10 supports HOT deployment of EAR files? Is it any issue with "Class Loading"? Anything to be changed to make this HOT redeployment successful?

App Server: WLS 10.3
OS: Solaris 9
I have installed WLS installed with a domain, admin and a managed server. Everything is working fine.
I have WAR and EAR deployed successfully on the Managed Server.
HOT deployment of WAR files works perfectly fine.
There is this EAR "IIA.ear" with @ 8 WAR files and 1 jar "Manager.jar". The EAR has been deployed in the "nostage" mode.
I do not have any separate "Deployment" plan.
In order to "redeploy" the EAR I go to the Admin console >> Deployments >> Select the EAR >> update >> Source Path remains the same >> Finish
I get the following error :
+#####################+
weblogic.application.CannotRedeployException: Module 'Manager.jar' has the same ClassLoader as the Application 'IIA'. Consider redeploying the entire application.
Update operation failed - no deployments changed.
+#####################+
The log files shows below error
+#####################+
+<Sep 15, 2009 9:18:52 AM MEST> <Error> <Deployer> <BEA-149265> <Failure occurred in the execution of deployment request with+
ID '1252999132033' for task '8'. Error is: 'weblogic.application.CannotRedeployException: Module 'Manager.jar' has the
same ClassLoader as the Application 'IIA'. Consider redeploying the entire application.'
weblogic.application.CannotRedeployException: Module 'Manager.jar' has the same ClassLoader as the Application 'IIA'. Consider redeploying the entire application.
at weblogic.application.internal.AppClassLoaderManagerImpl.updatePartialDeploySet(AppClassLoaderManagerImpl.java:299)
at weblogic.application.internal.flow.TailModuleRedeployFlow.validateClassLoaderStructure(TailModuleRedeployFlow.java
+:135)+
at weblogic.application.internal.flow.TailModuleRedeployFlow.validateRedeploy(TailModuleRedeployFlow.java:97)
at weblogic.application.internal.BaseDeployment$ValidateRedeployStateChange.next(BaseDeployment.java:801)
at weblogic.application.utils.StateMachineDriver.nextState(StateMachineDriver.java:37)
Truncated. see log file for complete stacktrace
+>+
+#####################+
does WLS 10 supports HOT deployment of EAR files? Is it any issue with "Class Loading"? Anything to be changed to make this HOT redeployment successful?

Loading an entire JAR via a classloader

Hi how would I load an entire JAR file via a classloader. Currently I'm able to load one file at a time (in this case org.w3c.dom.Node) as shown below:
import java.net.*;
public class MyJarLoader {
   public static void main(String [] args) throws Exception {
     URL[] urlsToLoadFrom = new URL[]{new URL("file:subdir3/xml-apis.jar")};
     URLClassLoader loader1 = new URLClassLoader(urlsToLoadFrom);
     Class cls1 = Class.forName("org.w3c.dom.Node", true, loader1);
     System.out.println("Loaded '"+cls1.getName()+"'");
     org.w3c.dom.Node Node = (org.w3c.dom.Node) cls1.newInstance();
Thanks

Figured this one out as below. Note this is the simplistic solution since it requires that the jar files be present in the classpath. If not, you will have to write your own loadClass method to read the data from the zip (& then can't use the method 'Class.forName()').
Regards
//Load Apache JAR files
URL[] urlArrToLoadFrom = new URL[]{new URL("file:xalan-j_2_5_0/xml-apis.jar"),
            new URL("file:xalan-j_2_5_0/xercesImpl.jar"), new URL("file:xalan-j_2_5_0/xalan.jar")};
//Create a URLClassLoader to access jar files
URLClassLoader urlLoaderGeneric = new URLClassLoader(urlArrToLoadFrom);
//Foreach jar file, open, load class files & close
for(int i=0; i<urlArrToLoadFrom.length; i++) {
//Debug
   System.out.println(urlArrToLoadFrom.toString());
   //Open zip file
   ZipFile zf = new ZipFile(urlArrToLoadFrom[i].getFile());
   for (Enumeration enum = zf.entries(); enum.hasMoreElements();) {
     //Get entry
     ZipEntry ze = (ZipEntry) enum.nextElement();
     //Only load if it's not a directory and it's a class file
     int iIndexClass = -1;
     if (!ze.isDirectory() && ((iIndexClass = ze.getName().indexOf(".class")) != -1)) {
         //Remove .class & replace / with .
         String strApacheClassName = (ze.getName().substring(0,iIndexClass)).replace('/','.');
         //Load class file
         Class classApache = Class.forName(strApacheClassName, true, urlLoaderGeneric);
         System.out.println("Loaded '"+classApache.getName()+"'");
   //Close zip
   zf.close();

Loading a jar via a custom classloader

Hi,
I have written a custom class loader that allows me to load a compiled java program as a collection of class files at runtime.
This is nice however I now need to consider the runtime execution of more complex java programs that have custom library dependencies.
This means loading a .jar library into the classloader. I can get the contents of a jar and load specific classes by name via reflection but I want to load the entire jar into the classloader so that its contents can be used 'as needed' much like a jar on the system classpath.
Is this possible? If so I would like to know how as I have been struggling with this problem and cannot see a solution.
Regards,
Stephen

However I still don't understand why you need to
actually load all those classes initially. Afterall,
URLClassLoader (which sounds a lot like what youare
describing) only loads classes as needed.i have just built a swing app that accesses an oracle
database, i jared together all the classes, and i did
something in the manfest file so that you can just
double clisk the jar and it fires up like an exe.
doing it this way everything is fine except it cannot
access the database, the reason is those oracle
classes are not loaded, even they are on the path - i
can run the app using a batch file but i dont like it
as it opens up a dos window. this is an example, as i
was told, where it is necessary to load all thoses
oracle database classes initially. Dear, daFei.
I believe that you are getting confused between the way the system will ignore that CLASPPATH environment variable when you run a java application packaged as a jar file with the -jar switch (the classpath for the jar can be set in the manifest) and what I am attempting to-do which is to run a compiled java program at runtime and dynamically load any dependant libraries.
Stephen

Replacing JAR files loaded by custom ClassLoader

Hi all,
I am trying to create an auto-updater for a stand alone application, which can look for new versions of relevant jar files on the internet and download them. I have code which will look for newly downloaded versions and can replace the old jar file with the new one (using simple File methods). This works fine for when the application is started initially, but as the application is a server and may not manually be started for a long time, I am trying to force the server to restart and reload with the new code.
if(newCode.exists()) {
     System.out.println("new code!");
     if(oldCode.exists()) {
          oldCode.delete();
     if(code.exists()) {
          if(! code.renameTo(oldCode)) {
                    throw new IOException("Error backing up code file");
     if(! newCode.renameTo(code)) {
          throw new IOException("Error installing new code file");
}I have looked around the forums a bit, and have come up with using a ClassLoader based on URLClassLoader:
class ProxyLoader extends URLClassLoader
     public ProxyLoader(String jarFile) throws MalformedURLException {
          super(new URL[] { (new File(jarFile)).toURL() });
     public Class findClass(String name) throws ClassNotFoundException {
          System.out.println("Finding: " + name);
          return super.findClass(name);
}This seems to work OK, as all the classes from the jar file are loaded by this classloader.
I have a method which can create an instance of the class loader, and load the server application.
private boolean startProxy(int port) {
     try {
          pl = new ProxyLoader("proxy.jar");
          Class ptClass = pl.loadClass("proxy.POPThread");
          pt = ptClass.newInstance();
          Method ptStart = ptClass.getMethod("start", new Class[0]);
          ptStart.invoke(pt, new Object[0]);
          return true;
     } catch(Exception e) {
          return false;
}I also have a method to shut down the server:
private boolean stopProxy() {
     try {
          Class ptClass = pl.loadClass("proxy.POPThread");
          Method ptInterrupt = ptClass.getMethod("interrupt", new Class[0]);
          ptInterrupt.invoke(pt, new Object[0]);
          return true;
     } catch(Exception e) {
          return false;
}These appear to be working fine, the problem I have however is when I try to rename the existing jar file (proxy.jar) in order to replace it with a new one (proxy.new), the renameTo method on the File object fails. I am guessing that is because the proxy.jar file is still in use by the JVM. I have tried setting the classloader var to null, but this doesnt seem to have any effect.
My main question is how can I 'free' the jar file so that it can be replaced with new code? Is it possible? My only otherway of working around this is to have a variable stored in a file pointing at the 'current' code, but the jar file isn't litterally replaced.
This is a standalone application, which will probably run in a startup script on a server, so webstart isn't really an option.
TIA
iklesteve

I have found this to be true anytime I try to use the renameTo() API to rename a file with a .jar file extension (regardless of the actual file type - i.e. it could be a text file with .jar appended and it will still fail) in the case where the class making the renameTo() call is loaded from another .jar file.
I run the same exact code after extracting from the .jar, then the rename to the other .jar file is successful. Also, if I rename the .jar file to a ".ja" file, I can successfully rename the jar file even if the code is running with the context of another .jar file.
Is this some kind of bogus security measure within the JVM or is it a bug?

Loading jar at runtime using custom classloader

Hi,
I'm trying to load a jar file to an application running inside weblogic at runtime.
I followed the example that was posted at
http://dev2dev.bea.com/cs/user/blog?file=/blog/jcscoobyrs/archive/2005/05/realworld_use_f.html
and did the following:
URLClassLoader loader = null;
URL[] urls = {new URL("file:///" + "C:/Program Files/aaa/WEB-INF/lib/ImportTest3.jar")};
ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
ClassLoader loader = new URLClassLoader(urls, classLoader);
Thread.currentThread().setContextClassLoader(loader);
Class customClass = Class.forName(className, true, loader);
customCode = customClass.newInstance();
Thread.currentThread().setContextClassLoader(classLoader);
everything works fine when I access my application once.
But when I'm trying to do the same again, everything fails.
Any ideas?
Thanks!

When you say everything fails - can you clarify the failure? Can you paste the stacktrace? Is it a ClassNotFoundException?

Problem with behavior of the Thread Context ClassLoader on OC4J 10.1.3.2.0

Hi,
We run into different behavior of the Thread Context ClassLoader on OC4J 10.1.3.1.0 (which is OK) and OC4J 10.1.3.2.0 (here we have problems). It appeared in the Threads directly and indirectly (e.g. through Timer) created by our application. Threads, created by OC4j (e.g. the Thread, where our start-up servlet are running) are OK.
Thread Context ClassLoader (could be received from Thread.currentThread().getContextClassLoader()) on OC4J 10.1.3.1.0 in all threads is the same ClassLoader instance as the current ClassLoader (could be received from getClass().getClassLoader()). Actually the same is true for JBoss, WebLogic and WebSphere.
Thread Context ClassLoader on OC4J 10.1.3.2.0 is NOT the same ClassLoader instance as the current ClassLoader, it is even the instance of the different Class. This ClassLoader does not see classes, available at application level, which causes multiple problems.
Is it possible to configure OC4J 10.1.3.2.0 to behave similar to OC4J 10.1.3.1.0?
We tried to use “–userThreads”, but it did not help.
To investigate this problem we created a simple Web Application, which has Start-up Servlet, creates one thread and one Timer Task. From each point it is checking if Thread Context ClassLoader is the same ClassLoader instance as the current ClassLoader and printing Class Loaders if they are different. In addition it checks if correct parser accessed (should be xerces, which is in the Web App classpath and for which we added a shared library). Below you could see what we received on OC4J 10.1.3.1.0 (which is OK) and OC4J 10.1.3.2.0:
E:\OracleAS_1\j2ee\home>java -Xms128m -Xmx1024m -jar oc4j.jar -userThreads
07/04/30 10:33:00 Oracle Containers for J2EE 10g (10.1.3.1.0) initialized
07/04/30 10:39:31 ------In StartupServlet Init-----
07/04/30 10:39:31 +++++++ ++++++++++++++++++++++++++++++++++++ ++++++++
07/04/30 10:39:31 +++++++ Executing Code in the StrtServlet... ++++++++
07/04/30 10:39:31 +++++++ (this Thread created by App Server) +++++++++
07/04/30 10:39:31 ClassLoaders: fromClass = getClass().getClassLoader() = <TestL
oaders.web.TestLoaders:0.0.0>*******<class oracle.classloader.PolicyClassLoader
07/04/30 10:39:31 fromThread =Thread.currentThread().getContextCla
ssLoader() = <TestLoaders.web.TestLoaders:0.0.0>*******<class oracle.classloader
.PolicyClassLoader
07/04/30 10:39:31 ******* THE SAME CLASSLOADER USED IN BOTH PLACES!!! *******
07/04/30 10:39:31 DocumentBuilderFactory = <org.apache.xerces.jaxp.DocumentBuild
erFactoryImpl@1908ba7>*******
07/04/30 10:39:31 C O R R E C T !!!
07/04/30 10:39:31 -CWD- =E:\OracleAS_1\j2ee\home; uer directory = E:\OracleAS_1\
j2ee\home
07/04/30 10:39:31 Constructing the Timer Task...
07/04/30 10:39:31 Starting some Timer...
07/04/30 10:39:31 Some Timer is started ...
07/04/30 10:39:31 ------All actions done Successfully--------
07/04/30 10:39:41 +++++++ +++++++++++++++++++++++++++++++++++ ++++++++
07/04/30 10:39:41 +++++++ Executing Code in the new Thread... ++++++++
07/04/30 10:39:41 ClassLoaders: fromClass = getClass().getClassLoader() = <TestL
oaders.web.TestLoaders:0.0.0>*******<class oracle.classloader.PolicyClassLoader
07/04/30 10:39:41 fromThread =Thread.currentThread().getContextCla
ssLoader() = <TestLoaders.web.TestLoaders:0.0.0>*******<class oracle.classloader
.PolicyClassLoader
07/04/30 10:39:41 ******* THE SAME CLASSLOADER USED IN BOTH PLACES!!! *******
07/04/30 10:39:41 DocumentBuilderFactory = <org.apache.xerces.jaxp.DocumentBuild
erFactoryImpl@17e5e56>*******
07/04/30 10:39:41 C O R R E C T !!!
07/04/30 10:40:31 +++++++ +++++++++++++++++++++++++++++++++++ ++++++++
07/04/30 10:40:31 +++++++ Executing the Session Timer Task... ++++++++
07/04/30 10:40:31 ClassLoaders: fromClass = getClass().getClassLoader() = <TestL
oaders.web.TestLoaders:0.0.0>*******<class oracle.classloader.PolicyClassLoader
07/04/30 10:40:31 fromThread =Thread.currentThread().getContextCla
ssLoader() = <TestLoaders.web.TestLoaders:0.0.0>*******<class oracle.classloader
.PolicyClassLoader
07/04/30 10:40:31 ******* THE SAME CLASSLOADER USED IN BOTH PLACES!!! *******
07/04/30 10:40:31 DocumentBuilderFactory = <org.apache.xerces.jaxp.DocumentBuild
erFactoryImpl@1c6988d>*******
07/04/30 10:40:31 C O R R E C T !!!
07/04/30 10:44:01 Shutting down OC4J...
07/04/30 10:44:01
E:\OracleAS_1\j2ee\home>
C:\oc4j\j2ee\home>java -Xms128m -Xmx1024m -classpath .;oc4j.jar;C:\oc4j\j2ee\hom
e\properties -Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socke
t,address=3999,server=y,suspend=n -jar oc4j.jar -userThreads
07/05/01 21:14:33 ------In StartupServlet Init-----
07/05/01 21:14:33 +++++++ ++++++++++++++++++++++++++++++++++++ ++++++++
07/05/01 21:14:33 +++++++ Executing Code in the StrtServlet... ++++++++
07/05/01 21:14:33 +++++++ (this Thread created by App Server) +++++++++
07/05/01 21:14:33 ClassLoaders: fromClass = getClass().getClassLoader() = <TestL
oaders.web.TestLoaders:0.0.0>*******<class oracle.classloader.PolicyClassLoader
07/05/01 21:14:33 fromThread =Thread.currentThread().getContextCla
ssLoader() = <TestLoaders.web.TestLoaders:0.0.0>*******<class oracle.classloader
.PolicyClassLoader
07/05/01 21:14:33 ******* THE SAME CLASSLOADER USED IN BOTH PLACES!!! *******
07/05/01 21:14:33 DocumentBuilderFactory = <org.apache.xerces.jaxp.DocumentBuild
erFactoryImpl@723c42>*******
07/05/01 21:14:33 C O R R E C T !!!
07/05/01 21:14:33 -CWD- =C:\oc4j\j2ee\home; uer directory = C:\oc4j\j2ee\home
07/05/01 21:14:33 Constructing the Timer Task...
07/05/01 21:14:33 Starting some Timer...
07/05/01 21:14:33 Some Timer is started ...
07/05/01 21:14:33 ------All actions done Successfully--------
07/05/01 21:14:33 Oracle Containers for J2EE 10g (10.1.3.2.0) initialized
07/05/01 21:14:43 +++++++ +++++++++++++++++++++++++++++++++++ ++++++++
07/05/01 21:14:43 +++++++ Executing Code in the new Thread... ++++++++
07/05/01 21:14:43 ClassLoaders: fromClass = getClass().getClassLoader() = <TestL
oaders.web.TestLoaders:0.0.0>*******<class oracle.classloader.PolicyClassLoader
07/05/01 21:14:43 fromThread =Thread.currentThread().getContextCla
ssLoader() = <[ThreadContextLoader, current context: TestLoaders.web.TestLoaders
:0.0.0]>*******<class com.evermind.server.ApplicationContextClassLoader
07/05/01 21:14:43 ******************************************************
07/05/01 21:14:43 Chain of ClassLoaders from Class
07/05/01 21:14:43 --- TestLoaders.root:0.0.0 --- class oracle.classloader.Polic
yClassLoader
07/05/01 21:14:43 --- default.root:0.0.0 --- class oracle.classloader.PolicyCla
ssLoader
07/05/01 21:14:43 --- system.root:0.0.0 --- class oracle.classloader.PolicyClas
sLoader
07/05/01 21:14:43 --- oc4j:10.1.3 --- class oracle.classloader.PolicyClassLoade
r
07/05/01 21:14:43 --- api:1.4.0 --- class oracle.classloader.PolicyClassLoader
07/05/01 21:14:43 --- jre.extension:0.0.0 --- class oracle.classloader.PolicyCl
assLoader
07/05/01 21:14:43 --- jre.bootstrap:1.4.2_08 --- class oracle.classloader.Polic
yClassLoader
07/05/01 21:14:43 --- null ---
07/05/01 21:14:43 ********** End of Chain of ClassLoaders **************
07/05/01 21:14:43 ******************************************************
07/05/01 21:14:43 Chain of ClassLoaders from Thread
07/05/01 21:14:43 --- oc4j:10.1.3 --- class oracle.classloader.PolicyClassLoade
r
07/05/01 21:14:43 --- api:1.4.0 --- class oracle.classloader.PolicyClassLoader
07/05/01 21:14:43 --- jre.extension:0.0.0 --- class oracle.classloader.PolicyCl
assLoader
07/05/01 21:14:43 --- jre.bootstrap:1.4.2_08 --- class oracle.classloader.Polic
yClassLoader
07/05/01 21:14:43 --- null ---
07/05/01 21:14:43 ********** End of Chain of ClassLoaders **************
07/05/01 21:14:43 DocumentBuilderFactory = <oracle.xml.jaxp.JXDocumentBuilderFac
tory@74a138>*******
07/05/01 21:14:43 WRONG !!! Should be org.apache.xerces.jaxp.DocumentBuilderFact
oryImpl
07/05/01 21:15:33 +++++++ +++++++++++++++++++++++++++++++++++ ++++++++
07/05/01 21:15:33 +++++++ Executing the Session Timer Task... ++++++++
07/05/01 21:15:33 ClassLoaders: fromClass = getClass().getClassLoader() = <TestL
oaders.web.TestLoaders:0.0.0>*******<class oracle.classloader.PolicyClassLoader
07/05/01 21:15:33 fromThread =Thread.currentThread().getContextCla
ssLoader() = <[ThreadContextLoader, current context: TestLoaders.web.TestLoaders
:0.0.0]>*******<class com.evermind.server.ApplicationContextClassLoader
07/05/01 21:15:33 **************************************************
07/05/01 21:15:33 Chain of ClassLoaders from Class
07/05/01 21:15:33 --- TestLoaders.root:0.0.0 --- class oracle.classloader.Polic
yClassLoader
07/05/01 21:15:33 --- default.root:0.0.0 --- class oracle.classloader.PolicyCla
ssLoader
07/05/01 21:15:33 --- system.root:0.0.0 --- class oracle.classloader.PolicyClas
sLoader
07/05/01 21:15:33 --- oc4j:10.1.3 --- class oracle.classloader.PolicyClassLoade
r
07/05/01 21:15:33 --- api:1.4.0 --- class oracle.classloader.PolicyClassLoader
07/05/01 21:15:33 --- jre.extension:0.0.0 --- class oracle.classloader.PolicyCl
assLoader
07/05/01 21:15:33 --- jre.bootstrap:1.4.2_08 --- class oracle.classloader.Polic
yClassLoader
07/05/01 21:15:33 --- null ---
07/05/01 21:15:33 ********** End of Chain of ClassLoaders **********
07/05/01 21:15:33 **************************************************
07/05/01 21:15:33 Chain of ClassLoaders from Thread
07/05/01 21:15:33 --- oc4j:10.1.3 --- class oracle.classloader.PolicyClassLoade
r
07/05/01 21:15:33 --- api:1.4.0 --- class oracle.classloader.PolicyClassLoader
07/05/01 21:15:33 --- jre.extension:0.0.0 --- class oracle.classloader.PolicyCl
assLoader
07/05/01 21:15:33 --- jre.bootstrap:1.4.2_08 --- class oracle.classloader.Polic
yClassLoader
07/05/01 21:15:33 --- null ---
07/05/01 21:15:33 ********** End of Chain of ClassLoaders **********
07/05/01 21:15:33 DocumentBuilderFactory = <oracle.xml.jaxp.JXDocumentBuilderFac
tory@1d12d43>*******
07/05/01 21:15:33 WRONG !!! Should be org.apache.xerces.jaxp.DocumentBuilderFact
oryImpl
Any help will be greatly appreciated.
Thanks

Sorry for confusion, version of OC4J does not really meter, but jdk does. It happened that in the case where everything OK (OC4J 10.1.3.1.0) I accidentally used jdk 1.5. Now I tried both (OC4J 10.1.3.1.0 and OC4J 10.1.3.2.0) with j2sdk1.4.2_14 (besides I tried j2sdk1.4.2_09 and _08) and j2sdk1.5.0_06.
With JDK 1.5 everything is OK and with JDK 1.4 we have a problem, described in the previous posting. I believe now I should reformulate my initial question:
Is it possible to configure OC4J 10.1.3 running under j2sdk1.4.2_14 to force Thread Context ClassLoader to behave similar to OC4J 10.1.3 under j2sdk1.5.0_06? If yes, how we could do it?
Thanks

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