java.lang.NullPointerException
   at java.awt.LinearGradientPaint.<init>(LinearGradientPaint.java:140)
   at javax.swing.plaf.nimbus.AbstractRegionPainter.decodeGradient(AbstractRegionPainter.java:380)
   at javax.swing.plaf.nimbus.ComboBoxPainter.decodeGradient6(ComboBoxPainter.java:639)
   at javax.swing.plaf.nimbus.ComboBoxPainter.paintBackgroundEnabled(ComboBoxPainter.java:293)
   at javax.swing.plaf.nimbus.ComboBoxPainter.doPaint(ComboBoxPainter.java:140)
   at javax.swing.plaf.nimbus.AbstractRegionPainter.paint0(AbstractRegionPainter.java:731)
   at javax.swing.plaf.nimbus.AbstractRegionPainter.getImage(AbstractRegionPainter.java:711)
   at javax.swing.plaf.nimbus.AbstractRegionPainter.paintWith9SquareCaching(AbstractRegionPainter.java:630)
   at javax.swing.plaf.nimbus.AbstractRegionPainter.paint(AbstractRegionPainter.java:159)
   at javax.swing.plaf.nimbus.AbstractRegionPainter.paint(AbstractRegionPainter.java:42)
   at javax.swing.plaf.nimbus.SynthPainterImpl.paint(SynthPainterImpl.java:61)
   at javax.swing.plaf.nimbus.SynthPainterImpl.paintBackground(SynthPainterImpl.java:101)
   at javax.swing.plaf.nimbus.SynthPainterImpl.paintComboBoxBackground(SynthPainterImpl.java:458)
   at javax.swing.plaf.synth.SynthComboBoxUI.update(SynthComboBoxUI.java:324)
   at javax.swing.JComponent.paintComponent(JComponent.java:779)
   at javax.swing.JComponent.paint(JComponent.java:1055)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at org.netbeans.core.windows.view.ui.toolbars.ToolbarContainer.paint(ToolbarContainer.java:327)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at org.netbeans.core.windows.view.ui.MainWindow$1.paint(MainWindow.java:189)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at javax.swing.JLayeredPane.paint(JLayeredPane.java:585)
   at javax.swing.JComponent.paintChildren(JComponent.java:888)
   at javax.swing.JComponent.paint(JComponent.java:1064)
   at javax.swing.JComponent.paintToOffscreen(JComponent.java:5232)
   at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1529)
   at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1452)
   at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:311)
   at javax.swing.RepaintManager.paint(RepaintManager.java:1249)
   at javax.swing.JComponent._paintImmediately(JComponent.java:5180)
   at javax.swing.JComponent.paintImmediately(JComponent.java:4991)
   at javax.swing.RepaintManager$3.run(RepaintManager.java:808)
   at javax.swing.RepaintManager$3.run(RepaintManager.java:796)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
   at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:796)
   at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:769)
   at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:718)
   at javax.swing.RepaintManager.access$1100(RepaintManager.java:62)
   at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1677)
   at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:312)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:745)
   at java.awt.EventQueue.access$300(EventQueue.java:103)
   at java.awt.EventQueue$3.run(EventQueue.java:706)
   at java.awt.EventQueue$3.run(EventQueue.java:704)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:715)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:159)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)