AppEngine error [java.lang.NoClassDefFoundError: org / w3c / dom / ElementTraversal]

Question

I was looking to find a solution to this problem, but it seems difficult. I have an appengine project working with a servlet that handles registration. When I try to call this servlet, I have this log report:

012-04-19 10:31:06.816 /register 500 90ms 0kb Apache-HttpClient/UNAVAILABLE (java 1.4) ip - gecodroidtest [19/Apr/2012:10:31:06 -0700] "POST /register HTTP/1.1" 500 0 - "Apache-HttpClient/UNAVAILABLE (java 1.4)" "cloudnotifyit.appspot.com" ms=90 cpu_ms=58 api_cpu_ms=0 cpm_usd=0.001738 instance=00c61b117c772731eb45290bfcb07750c0505f W 2012-04-19 10:31:06.794 com.cloudnotify.server.servlet.RequestInfo processRequest: xxxxxxxxxxxx@xxxx //just for me W 2012-04-19 10:31:06.810 Error for /register java.lang.NoClassDefFoundError: org/w3c/dom/ElementTraversal at com.google.appengine.runtime.Request.process-240c2ffe1bf8ddba(Request.java) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:634) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:277) at sun.reflect.GeneratedMethodAccessor5.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at java.lang.ClassLoader.loadClass(ClassLoader.java:266) at org.apache.xerces.parsers.AbstractDOMParser.startDocument(Unknown Source) at org.apache.xerces.impl.dtd.XMLDTDValidator.startDocument(Unknown Source) at org.apache.xerces.impl.XMLDocumentScannerImpl.startEntity(Unknown Source) at org.apache.xerces.impl.XMLVersionDetector.startDocumentParsing(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XMLParser.parse(Unknown Source) at org.apache.xerces.parsers.DOMParser.parse(Unknown Source) at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source) at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:121) at javax.jdo.JDOHelper.readNamedPMFProperties(JDOHelper.java:1407) at javax.jdo.JDOHelper.getNamedPMFProperties(JDOHelper.java:1286) at javax.jdo.JDOHelper.getPropertiesFromJdoconfig(JDOHelper.java:1232) at javax.jdo.JDOHelper.getPersistenceManagerFactory(JDOHelper.java:1079) at javax.jdo.JDOHelper.getPersistenceManagerFactory(JDOHelper.java:914) at com.cloudnotify.server.c2dm.C2DMessaging.getPMF(C2DMessaging.java:103) at com.cloudnotify.server.servlet.RequestInfo.initDevices(RequestInfo.java:225) at com.cloudnotify.server.servlet.RequestInfo.processRequest(RequestInfo.java:183) at com.cloudnotify.server.servlet.RegisterServlet.doPost(RegisterServlet.java:100) at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:326) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) at com.google.tracing.TraceContext$TraceContextRunnable.runInContext(TraceContext.java:449) at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:455) at com.google.tracing.TraceContext.runInContext(TraceContext.java:695) at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:333) at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:325) at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:453) at java.lang.Thread.run(Thread.java:679) Caused by: java.lang.ClassNotFoundException: org.w3c.dom.ElementTraversal at com.google.appengine.runtime.Request.process-240c2ffe1bf8ddba(Request.java) ... 44 more C 2012-04-19 10:31:06.812 Uncaught exception from servlet java.lang.NoClassDefFoundError: org/w3c/dom/ElementTraversal at com.google.appengine.runtime.Request.process-240c2ffe1bf8ddba(Request.java) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:634) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) at java.net.URLClassLoader.defineClass(URLClassLoader.java:277) at sun.reflect.GeneratedMethodAccessor5.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at java.lang.ClassLoader.loadClass(ClassLoader.java:266) at org.apache.xerces.parsers.AbstractDOMParser.startDocument(Unknown Source) at org.apache.xerces.impl.dtd.XMLDTDValidator.startDocument(Unknown Source) at org.apache.xerces.impl.XMLDocumentScannerImpl.startEntity(Unknown Source) at org.apache.xerces.impl.XMLVersionDetector.startDocumentParsing(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XMLParser.parse(Unknown Source) at org.apache.xerces.parsers.DOMParser.parse(Unknown Source) at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source) at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:121) at javax.jdo.JDOHelper.readNamedPMFProperties(JDOHelper.java:1407) at javax.jdo.JDOHelper.getNamedPMFProperties(JDOHelper.java:1286) at javax.jdo.JDOHelper.getPropertiesFromJdoconfig(JDOHelper.java:1232) at javax.jdo.JDOHelper.getPersistenceManagerFactory(JDOHelper.java:1079) at javax.jdo.JDOHelper.getPersistenceManagerFactory(JDOHelper.java:914) at com.cloudnotify.server.c2dm.C2DMessaging.getPMF(C2DMessaging.java:103) at com.cloudnotify.server.servlet.RequestInfo.initDevices(RequestInfo.java:225) at com.cloudnotify.server.servlet.RequestInfo.processRequest(RequestInfo.java:183) at com.cloudnotify.server.servlet.RegisterServlet.doPost(RegisterServlet.java:100) at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:326) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) at com.google.tracing.TraceContext$TraceContextRunnable.runInContext(TraceContext.java:449) at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:455) at com.google.tracing.TraceContext.runInContext(TraceContext.java:695) at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:333) at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:325) at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:453) at java.lang.Thread.run(Thread.java:679) Caused by: java.lang.ClassNotFoundException: org.w3c.dom.ElementTraversal at com.google.appengine.runtime.Request.process-240c2ffe1bf8ddba(Request.java) ... 44 more Thanks all 

Answer 1

There may be a problem with the Xerces parser in GAE. See http://code.google.com/p/googleappengine/issues/detail?id=1367

Perhaps a workaround is to ensure that all Xerces banks (including xml-apis.jar) are in your WEB-INF / lib.

Answer 2

• MAVEN SOLUTION:

In pom.xml, set the "xml-apis" parameter to version 1.4.01:

 <dependency> <groupId>xml-apis</groupId> <artifactId>xml-apis</artifactId> <version>1.4.01</version> </dependency> 

• SOLUTION FOR ALL ELSE:

If you are not using maven, you can manually add the xml-apis library, version 1.4.01. You will find banks in the xml-commons binary package called "XML Commons External 1.4.01", and you can download it here: http://xerces.apache.org/mirrors.cgi .

Finally, compile and execute your java application / project with this version of the library.

• Explanation:

The version of the xml-apis library version 1.4.01 includes the necessary ElementTraversal class. Other versions, such as 2.0.0, 1.0.0, etc., do not include it, and the application fails to compile.

Answer 3

Your problem can be solved by updating to version 2.11.0.SP5 , which already contains the ElementTraversal class.