Question

I have also posted this question on the netbeans forums – hoping for maximum exposure.

I am developing an application using NetBeans RELEASE67 and maven-nbm plugin.
I use Java WebStart to deploy.

My users have a mixture of java 1.6 and java 1.5

My java 1.5 users are unable to use the software;
on startup the software calls TopComponent.findInstance()
and this results in


java.lang.NoClassDefFoundError: javax/swing/GroupLayout$Group


I can see that javax.swing.GroupLayout is new to java 1.6+, and am stumped that the basic TopComponent code is so tied to java 1.6.

How can I get a NetBeans platform app to run under Java 1.5?

I will try to rewind to RELEASE65 in the hope this will solve the problem.
Any suggestions?

Thanks alot.

Answer 1

Apologies for the slow response.

My problem was that I was running the IDE under Java 6, and Matisse had created all the layouts using the java6 only class javax.swing.GroupLayout.

I didn’t notice the problem until I had to run the software on the minoritiy of my clients who are stuck on Java 1.5

This is easily fixed using the following procedure

• Open the TopComponent in the ‘Inspector’ window
• Right-click on the root node (Form TopComponent). Select the ‘Properties Windo
• In the properties window there is a line about ‘Layout Generation Style’. The choice is between
  • Standard Java 6 Code
  • Swing Layout Extensions Library
• Select the latter option.
• Rebuild