NoClassDefFoundError: javax/swing/GroupLayout$Group on Mac Computer

Question

I am having a runtime error ONLY when I test my Java program on a mac computer. It tests perfectly fine on various Windows operating systems. This is the error message I get on a Mac computer...

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: javax/swing/GroupLayout$Group at project.MainPanel.calculateButtonActionPerformed(MainPanel.java:198) at project.MainPanel.access$200(MainPanel.java:32) at project.MainPanel$3.actionPerformed(MainPanel.java:97) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1882) at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2202) at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420) at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258) at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236) at java.awt.Component.processMouseEvent(Component.java:5602) at javax.swing.JComponent.processMouseEvent(JComponent.java:3135) at java.awt.Component.processEvent(Component.java:5367) at java.awt.Container.processEvent(Container.java:2010) at java.awt.Component.dispatchEventImpl(Component.java:4068) at java.awt.Container.dispatchEventImpl(Container.java:2068) at java.awt.Component.dispatchEvent(Component.java:3903) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4256) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3936) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3866) at java.awt.Container.dispatchEventImpl(Container.java:2054) at java.awt.Window.dispatchEventImpl(Window.java:1801) at java.awt.Component.dispatchEvent(Component.java:3903) at java.awt.EventQueue.dispatchEvent(EventQueue.java:463) at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatch! Thread.j ava:269) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:184) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:176) at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)\

I do not know why this is happening. Could the fact that I compiled the program on a Windows computer be the problem? That is the only thing that I could think of.

Answer 1

Without being able to test this, I would assume that this is because the Java version that you compiled this under is greater than the Java version that you are running on your Macintosh.

I suggest that you check the versions of each and make sure that the version which you are running under Mac OS is the same, or later.

Alternatively, you could try using the "-target" option for javac to set an older version and see if that helps.

Answer 2

Under OS X the default version of Java is Java 1.5.

The only good Way to ensure the right jvm is with java Web start.