Classloader issue in WebSphere Application server 7.x - jsf

Question

com.ibm.xml.xlxp2.api.stax.XMLOutputFactoryImpl incompatible with
javax.xml.stream.XMLOutputFactory
com.ibm.xml.xlxp2.api.stax.XMLOutputFactoryImpl incompatible with
javax.xml.stream.XMLInputFactory
Removed "jsr173_1.0_api.jar", "stax-api-1.0-2.jar" that has "XMLOutputFactory" and "XMLInputFactory" classes from APP(Web-inf/lib) to avoid any collision with server versions.
Also changed the war class loader order to "parent last" and
policy to "Single class loader for application" in WebSphere admin
console. Have made this change to give priority to application jars WebInf/lib than server jars.
Below is the stack-trace.
java.lang.ClassCastException: com.ibm.xml.xlxp2.api.stax.XMLOutputFactoryImpl incompatible with javax.xml.stream.XMLOutputFactory
javax.faces.FacesException: #{tBean.persist}: java.lang.ClassCastException: com.ibm.xml.xlxp2.api.stax.XMLOutputFactoryImpl incompatible with javax.xml.stream.XMLOutputFactory
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:118)
at javax.faces.component.UICommand.broadcast(UICommand.java:315)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1655)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1595)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:131)
at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79)
at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:188)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:116)
at com.testtech.myapp.admin.authentication.UrlAuthorization.doFilter(Unknown Source)
at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:188)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:116)
at com.testtech.myapp.admin.authentication.UrlAuthentication.doFilter(Unknown Source)
at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:188)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:116)
at com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:114)
at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:188)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:116)
at com.ibm.ws.webcontainer.filter.WebAppFilterChain._doFilter(WebAppFilterChain.java:77)
at com.ibm.ws.webcontainer.filter.WebAppFilterManager.doFilter(WebAppFilterManager.java:895)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:932)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:500)
at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:178)
at com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest(CacheServletWrapper.java:91)
at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:864)
at com.ibm.ws.webcontainer.WSWebContainer.handleRequest(WSWebContainer.java:1583)
at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:183)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:455)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation(HttpInboundLink.java:384)
at com.ibm.ws.http.channel.inbound.impl.HttpICLReadCallback.complete(HttpICLReadCallback.java:83)
at com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:165)
at com.ibm.io.async.AbstractAsyncFuture.invokeCallback(AbstractAsyncFuture.java:217)
at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions(AsyncChannelFuture.java:161)
at com.ibm.io.async.AsyncFuture.completed(AsyncFuture.java:138)
at com.ibm.io.async.ResultHandler.complete(ResultHandler.java:204)
at com.ibm.io.async.ResultHandler.runEventProcessingLoop(ResultHandler.java:775)
at com.ibm.io.async.ResultHandler$2.run(ResultHandler.java:905)
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1550)
Caused by: javax.faces.el.EvaluationException: java.lang.ClassCastException: com.ibm.xml.xlxp2.api.stax.XMLOutputFactoryImpl incompatible with javax.xml.stream.XMLOutputFactory
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102)
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
... 42 more
Caused by: java.lang.ClassCastException: com.ibm.xml.xlxp2.api.stax.XMLOutputFactoryImpl incompatible with javax.xml.stream.XMLOutputFactory
at javax.xml.stream.XMLOutputFactory.newInstance(XMLOutputFactory.java:98)
at com.thoughtworks.xstream.io.xml.StaxDriver.getOutputFactory(StaxDriver.java:157)
at com.thoughtworks.xstream.io.xml.StaxDriver.createWriter(StaxDriver.java:109)
at com.thoughtworks.xstream.XStream.toXML(XStream.java:802)
at com.thoughtworks.xstream.XStream.toXML(XStream.java:792)
at com.testtech.UI.z.service.zService.createz(Unknown Source)
at com.testtech.UI.z.web.zBean.persist(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
at java.lang.reflect.Method.invoke(Method.java:600)
at com.sun.el.parser.AstValue.invoke(AstValue.java:234)
at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:297)
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
... 43 more
JSF2.1.2
Spring 3.1.0
Prettyfaces-jsf2-3.3.2
Primefaces 3.2
WebSphere Application Server 7.0.0.9
ibm page
When troubleshooting class loading problems, you might need to
override classes visible to a parent class loader. To override such
classes with those specific to an application, set the Class loader
mode to Parent last on the class loader that contains the application
classes on its classpath. An application can override classes visible
to a parent class loader, but doing so can result in a
ClassCastException or UnsatisfiedLinkError if there is a mixed use of
overridden classes and non-overridden classes.

Answer 1

You are using a third party JSF implementation. As a first step I'd suggest you to check if you have configured it right. Here is the infocenter link for Configuring JavaServer Faces implementation.
Basically you must
create an isolated shared library
put your JSF libraries and its dependencies in it
associate shared library with your module
set application classloader policy to PARENTLAST