OPERATING SYSTEM
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All

FULL JDK VERSION
----------------
1.6.0_10 onwards.

DESCRIPTION
-----------
This looks similar to CR 6785663, but the stack traces are different.

Load the Java 2D Demo application using the Swing Nimbus Look and feel:

java -jar -Dswing.defaultlaf=com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel Java2Demo.jar

On opening and closing the application several times the problem will be seen. We different Exceptions on different platforms:

Linux
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Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: java.lang.Boolean cannot be cast to java.awt.Color
        at com.sun.java.swing.plaf.nimbus.NimbusStyle.getColorForState(NimbusStyle.java:670)
        at javax.swing.plaf.synth.SynthStyle.getColor(SynthStyle.java:783)
        at javax.swing.plaf.synth.SynthLookAndFeel.paintRegion(SynthLookAndFeel.java:387)
        at javax.swing.plaf.synth.SynthLookAndFeel.update(SynthLookAndFeel.java:351)
        at javax.swing.plaf.synth.SynthPanelUI.update(SynthPanelUI.java:94)
        at javax.swing.JComponent.paintComponent(JComponent.java:763)
        at javax.swing.JComponent.paint(JComponent.java:1027)
        at javax.swing.JComponent.paintToOffscreen(JComponent.java:5122)
        at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:277)
        at javax.swing.RepaintManager.paint(RepaintManager.java:1217)
        at javax.swing.JComponent._paintImmediately(JComponent.java:5070)
        at javax.swing.JComponent.paintImmediately(JComponent.java:4880)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:803)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:714)
        at javax.swing.RepaintManager.seqPaintDirtyRegions(RepaintManager.java:694)
        at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:128)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: com.sun.java.swing.plaf.nimbus.DerivedColor$UIResource cannot be cast to com.sun.java.swing.Painter
        at com.sun.java.swing.plaf.nimbus.NimbusStyle.getBorderPainter(NimbusStyle.java:903)
        at com.sun.java.swing.plaf.nimbus.SynthPainterImpl.paintBorder(SynthPainterImpl.java:102)
        at com.sun.java.swing.plaf.nimbus.SynthPainterImpl.paintPanelBorder(SynthPainterImpl.java:960)
        at javax.swing.plaf.synth.SynthPanelUI.paintBorder(SynthPanelUI.java:114)
        at javax.swing.plaf.synth.SynthBorder.paintBorder(SynthBorder.java:46)
        at javax.swing.JComponent.paintBorder(JComponent.java:922)
        at javax.swing.JComponent.paint(JComponent.java:1028)
        at javax.swing.JComponent.paintToOffscreen(JComponent.java:5122)
        at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:277)
        at javax.swing.RepaintManager.paint(RepaintManager.java:1217)
        at javax.swing.JComponent._paintImmediately(JComponent.java:5070)
        at javax.swing.JComponent.paintImmediately(JComponent.java:4880)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:803)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:714)
        at javax.swing.RepaintManager.seqPaintDirtyRegions(RepaintManager.java:694)
        at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:128)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

Windows
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Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: javax.swing.plaf.FontUIResource cannot be cast to com.sun.java.swing.Painter
        at com.sun.java.swing.plaf.nimbus.NimbusStyle.getBackgroundPainter(NimbusStyle.java:829)
        at com.sun.java.swing.plaf.nimbus.SynthPainterImpl.paintBackground(SynthPainterImpl.java:85)
        at com.sun.java.swing.plaf.nimbus.SynthPainterImpl.paintPanelBackground(SynthPainterImpl.java:943)
        at javax.swing.plaf.synth.SynthPanelUI.update(SynthPanelUI.java:95)
        at javax.swing.JComponent.paintComponent(JComponent.java:763)
        at javax.swing.JComponent.paint(JComponent.java:1029)
        at javax.swing.JComponent.paintToOffscreen(JComponent.java:5124)
        at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:277)
        at javax.swing.RepaintManager.paint(RepaintManager.java:1220)
        at javax.swing.JComponent._paintImmediately(JComponent.java:5072)
        at javax.swing.JComponent.paintImmediately(JComponent.java:4882)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:803)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:714)
        at javax.swing.RepaintManager.seqPaintDirtyRegions(RepaintManager.java:694)
        at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:128)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

Though the exceptions are thrown the GUI is able to load successfully and there is no effect on the functionality of the application. The problem is intermittent in nature.