Exception occurs in GUI Builder in NetBeans : java.lang.ClassNotFoundException: org.w3c.dom.ElementTraversal

[Peter Quiring]

NetBeans 7.0.1 fails to open GUI Builder for JPanels / JFrames / etc.
An exception occurs rendering NetBeans useless.
Using Ubuntu 12.04 beta 1
I've used NetBeans downloaded from their website in the past, so the problem must be in Ubuntu's package.

Thanks.

Here is the full exception:

java.lang.ClassNotFoundException: org.w3c.dom.ElementTraversal
 at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
 at java.security.AccessController.doPrivileged(Native Method)
 at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
 at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
Caused: java.lang.ClassNotFoundException: org.w3c.dom.ElementTraversal starting from ModuleCL@36d047[org.netbeans.libs.xerces] with possible defining loaders [ModuleCL@9c176c[org.netbeans.modules.swingapp]] and declared parents []
 at org.netbeans.ProxyClassLoader.loadClass(Unknown Source)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
Caused: java.lang.NoClassDefFoundError: org/w3c/dom/ElementTraversal
 at java.lang.ClassLoader.defineClass1(Native Method)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:634)
 at org.netbeans.JarClassLoader.doLoadClass(Unknown Source)
Caused: java.lang.NoClassDefFoundError: org/w3c/dom/ElementTraversal while loading org.apache.xerces.dom.ElementImpl; see http://wiki.netbeans.org/DevFaqTroubleshootClassNotFound
 at org.netbeans.ProxyClassLoader.selfLoadClass(Unknown Source)
 at org.netbeans.ProxyClassLoader.loadClass(Unknown Source)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
 at java.lang.ClassLoader.defineClass1(Native Method)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:634)
 at org.netbeans.JarClassLoader.doLoadClass(Unknown Source)
Caused: java.lang.NoClassDefFoundError: org/w3c/dom/ElementTraversal while loading org.apache.xerces.dom.ElementImpl; see http://wiki.netbeans.org/DevFaqTroubleshootClassNotFound while loading org.apache.xerces.dom.ElementNSImpl; see http://wiki.netbeans.org/DevFaqTroubleshootClassNotFound
 at org.netbeans.ProxyClassLoader.selfLoadClass(Unknown Source)
 at org.netbeans.ProxyClassLoader.loadClass(Unknown Source)
 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.netbeans.modules.form.GandalfPersistenceManager.canLoadForm(Unknown Source)
 at org.netbeans.modules.form.FormDesigner$PreLoadTask.getPersistenceManager(Unknown Source)
 at org.netbeans.modules.form.FormDesigner$PreLoadTask.run(Unknown Source)
[catch] at org.openide.util.RequestProcessor$Task.run(Unknown Source)
 at org.openide.util.RequestProcessor$Processor.run(Unknown Source)

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: openjdk-6-jre-headless 6b24-1.11.1-3ubuntu2
ProcVersionSignature: Ubuntu 3.2.0-17.27-generic-pae 3.2.6
Uname: Linux 3.2.0-17-generic-pae i686
NonfreeKernelModules: nvidia
ApportVersion: 1.93-0ubuntu2
Architecture: i386
Date: Fri Mar 2 09:36:20 2012
ExecutablePath: /usr/lib/jvm/java-6-openjdk-i386/jre/bin/java
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Beta i386 (20120301)
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, user)
 LANG=en_US.UTF-8
SourcePackage: openjdk-6
UpgradeStatus: No upgrade log present (probably fresh install)

[Peter Quiring (pquiring)]

FYI : I downloaded 7.1.1 from netbeans.org and it works fine.
When I use Ubuntu version it says "Loading..." on the JPanel but the exception occurs and stops Loading so you can't use the GUI builder.

[Peter Quiring (pquiring)]

Also the netbeans that I download from netbeans.org doesn't appear in the ALT+TAB list. So once I minimize it there is no way to switch back to it and I have to "killall java" and restart.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[David Gnedt (lxp13)]

I have exactly the same problem in Ubuntu 12.04 Beta 2 (Netbeans 7.0.1+dfsg1-4)

Starting Netbeans with the following command fixes the problem for me:
$ netbeans --cp:a /usr/share/java/xercesImpl.jar

The corresponding bug at Debian:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=653915

[Maarten Bezemer (veger)]

Thanks for taking the time to report this bug in the upstream bug tracking system this is a tremendous help. Launchpad has the ability to watch lots of upstream bug trackers and this can be done by following the procedure documented at https://wiki.ubuntu.com/Bugs/Watches. I've added the bug watch for this bug report.

[David Gnedt (lxp13)]

Looks like xercesImpl.jar is not the only missing library. I also needed to manually add /usr/share/java/svn-javahl.jar to the class path to get a working subversion support in Netbeans.

[sde (sde)]

Lubuntu still distributes 7.0.1 as its NetBeans package. The suggested fix worked, so I put it in my start menu shortcut as:

/usr/bin/netbeans -cp:a /usr/share/java/xercesImpl.jar