Why do I get a NoClassDefFound error when I try to save my test plan?

Question

I installed apache-jmeter-5.1.1 and java 1.8.0_221 (8), and was walking through the getting started guide to build a web test plan in the GUI. But when I click save to save the Test Plan I receive the below error:

Uncaught Exception java.lang.NoClassDefFoundError: Could not initialize class org.apache.jmeter.gui.util.FileDialoger. See log file for details.

Full Output in debugger:

2019-07-24 15:30:13,306 ERROR o.a.j.JMeter: Uncaught exception: 
java.lang.NoClassDefFoundError: Could not initialize class org.apache.jmeter.gui.util.FileDialoger
    at org.apache.jmeter.gui.action.Save.computeFileName(Save.java:203) ~[ApacheJMeter_core.jar:5.1.1 r1855137]
    at org.apache.jmeter.gui.action.Save.doAction(Save.java:165) ~[ApacheJMeter_core.jar:5.1.1 r1855137]
    at org.apache.jmeter.gui.action.ActionRouter.performAction(ActionRouter.java:88) ~[ApacheJMeter_core.jar:5.1.1 r1855137]
    at org.apache.jmeter.gui.action.ActionRouter.lambda$actionPerformed$0(ActionRouter.java:70) ~[ApacheJMeter_core.jar:5.1.1 r1855137]
    at java.awt.event.InvocationEvent.dispatch(Unknown Source) ~[?:1.8.0_221]
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source) ~[?:1.8.0_221]
    at java.awt.EventQueue.access$500(Unknown Source) ~[?:1.8.0_221]
    at java.awt.EventQueue$3.run(Unknown Source) ~[?:1.8.0_221]
    at java.awt.EventQueue$3.run(Unknown Source) ~[?:1.8.0_221]
    at java.security.AccessController.doPrivileged(Native Method) ~[?:1.8.0_221]
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source) ~[?:1.8.0_221]
    at java.awt.EventQueue.dispatchEvent(Unknown Source) ~[?:1.8.0_221]
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source) [?:1.8.0_221]
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source) [?:1.8.0_221]
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source) [?:1.8.0_221]
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source) [?:1.8.0_221]
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source) [?:1.8.0_221]
    at java.awt.EventDispatchThread.run(Unknown Source) [?:1.8.0_221]

Any idea how to resolve?

Holloman

Possible duplicate of java.lang.NoClassDefFoundError: Could not initialize class org.apache.jmeter.gui.util.MenuFactory – Arva

@matiaselgart Fresh install, I haven't been adding/changing any of the files in JMeter – Holloman

i would double, triple check your classpath as you're running JMeter. Seems like a missing or conflicting jar type of issue. Sorry can't be of more help. – Arva

Answer 1

Try the following:

1. Open JMeter -> Options -> Look and Feel -> Select any other theme other than Darcula.
2. Restart JMeter, Create test plan and try to save.
3. Save should work.

Anyplace

I needed to use "Metal" as many of the others on MacOS were still failing with the same error as the Darcula one. Metal is always available as it is the JDK default theme that has been around forever. – Collaborationist

"System" worked for me in mac Monterey – Muir