In running a
transform, we occasionally get the error below. This is only during a stress
test, and happens perhaps once per several 100 transforms. Any idea how we can
determine what the problem is? We get a similar problem (although not from a
NullPointerException) in a different stylesheet as well, so it doesn't seem to
be tied to the stylesheet.
The application is
performing the transforms in a thread-safe manner, by caching the Templates
object and getting a new transformer for each invocation of the
transform.
Any ideas are most
appreciated.
Thanks,
Cory
javax.xml.transform.TransformerException: Unknown
error in XPath.
at org.apache.xpath.XPath.execute(XPath.java:334)
at org.apache.xalan.templates.ElemVariable.getValue(ElemVariable.java:316)
at org.apache.xalan.templates.ElemVariable.execute(ElemVariable.java:284)
at org.apache.xalan.templates.ElemForEach.transformSelectedNodes(ElemForEach.java:423)
at org.apache.xalan.templates.ElemForEach.execute(ElemForEach.java:284)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemTemplate.execute(ElemTemplate.java:431)
at org.apache.xalan.templates.ElemCallTemplate.execute(ElemCallTemplate.java:274)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemLiteralResult.execute(ElemLiteralResult.java:696)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemLiteralResult.execute(ElemLiteralResult.java:696)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemTemplate.execute(ElemTemplate.java:431)
at org.apache.xalan.templates.ElemCallTemplate.execute(ElemCallTemplate.java:274)
at org.apache.xalan.templates.ElemApplyTemplates.transformSelectedNodes(ElemApplyTemplates.java:425)
at org.apache.xalan.templates.ElemApplyTemplates.execute(ElemApplyTemplates.java:215)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.transformer.TransformerImpl.applyTemplateToNode(TransformerImpl.java:2185)
at org.apache.xalan.transformer.TransformerImpl.transformNode(TransformerImpl.java:1263)
at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:671)
at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1179)
at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1157)
at com.compuflex.framework.gui.taglib.ControlGroupTag.doStartTag(ControlGroupTag.java:293)
at org.apache.jsp.vpSLVFrame_jsp._jspx_meth_fw_controlgroup_0(vpSLVFrame_jsp.java:230)
at org.apache.jsp.vpSLVFrame_jsp._jspService(vpSLVFrame_jsp.java:101)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:137)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:210)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2416)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:601)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:392)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:565)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619)
at java.lang.Thread.run(Thread.java:536)
Caused by: java.lang.NullPointerException
---------
java.lang.NullPointerException
at org.apache.xpath.XPath.execute(XPath.java:334)
at org.apache.xalan.templates.ElemVariable.getValue(ElemVariable.java:316)
at org.apache.xalan.templates.ElemVariable.execute(ElemVariable.java:284)
at org.apache.xalan.templates.ElemForEach.transformSelectedNodes(ElemForEach.java:423)
at org.apache.xalan.templates.ElemForEach.execute(ElemForEach.java:284)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemTemplate.execute(ElemTemplate.java:431)
at org.apache.xalan.templates.ElemCallTemplate.execute(ElemCallTemplate.java:274)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemLiteralResult.execute(ElemLiteralResult.java:696)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemLiteralResult.execute(ElemLiteralResult.java:696)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.templates.ElemTemplate.execute(ElemTemplate.java:431)
at org.apache.xalan.templates.ElemCallTemplate.execute(ElemCallTemplate.java:274)
at org.apache.xalan.templates.ElemApplyTemplates.transformSelectedNodes(ElemApplyTemplates.java:425)
at org.apache.xalan.templates.ElemApplyTemplates.execute(ElemApplyTemplates.java:215)
at org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2318)
at org.apache.xalan.transformer.TransformerImpl.applyTemplateToNode(TransformerImpl.java:2185)
at org.apache.xalan.transformer.TransformerImpl.transformNode(TransformerImpl.java:1263)
at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:671)
at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1179)
at org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1157)
at com.compuflex.framework.gui.taglib.ControlGroupTag.doStartTag(ControlGroupTag.java:293)
at org.apache.jsp.vpSLVFrame_jsp._jspx_meth_fw_controlgroup_0(vpSLVFrame_jsp.java:230)
at org.apache.jsp.vpSLVFrame_jsp._jspService(vpSLVFrame_jsp.java:101)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:137)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:210)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2416)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:601)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:392)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:565)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619)
at java.lang.Thread.run(Thread.java:536)
Caused by: java.lang.NullPointerException
---------
java.lang.NullPointerException
Cory Isaacson
Vice President Product
Management
Quovadx, Inc.
(818) 884-1168
