NullPointerException at org.jdesktop.swingx.JXPanel.paint(JXPanel.java:592) + SynthTabbedPaneUI

[homebeaver]

reproduce:

• open SwingSet Demos
• switch to Nimbus
• start XTree Demo
• switch back to Metal (XTree Panel ist still Nimbus)
• focus XTree Panel ===> exception

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: Cannot invoke "java.awt.Font.hashCode()" because "font" is null
at java.desktop/sun.font.FontDesignMetrics$MetricsKey.init(FontDesignMetrics.java:219)
at java.desktop/sun.font.FontDesignMetrics.getMetrics(FontDesignMetrics.java:288)
at java.desktop/sun.swing.SwingUtilities2.getFontMetrics(SwingUtilities2.java:1242)
at java.desktop/javax.swing.JComponent.getFontMetrics(JComponent.java:1691)
at java.desktop/sun.swing.SwingUtilities2.getFontMetrics(SwingUtilities2.java:355)
at java.desktop/javax.swing.plaf.synth.SynthTabbedPaneUI.paintTab(SynthTabbedPaneUI.java:648)
at java.desktop/javax.swing.plaf.synth.SynthTabbedPaneUI.paintTabArea(SynthTabbedPaneUI.java:548)
at java.desktop/javax.swing.plaf.synth.SynthTabbedPaneUI.paint(SynthTabbedPaneUI.java:486)
at java.desktop/javax.swing.plaf.synth.SynthTabbedPaneUI.update(SynthTabbedPaneUI.java:384)
at java.desktop/javax.swing.JComponent.paintComponent(JComponent.java:842)
at java.desktop/javax.swing.JComponent.paint(JComponent.java:1119)
at java.desktop/javax.swing.JComponent.paintChildren(JComponent.java:952)
at java.desktop/javax.swing.JComponent.paint(JComponent.java:1128)
at org.jdesktop.swingx.JXPanel.paint(JXPanel.java:592) <===================
at java.desktop/javax.swing.JComponent.paintToOffscreen(JComponent.java:5311)
at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBufferedFPScales(RepaintManager.java:1721)
at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1630)
at java.desktop/javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1570)
at java.desktop/javax.swing.RepaintManager.paint(RepaintManager.java:1337)
at java.desktop/javax.swing.JComponent._paintImmediately(JComponent.java:5259)
at java.desktop/javax.swing.JComponent.paintImmediately(JComponent.java:5069)
at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:879)
at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:862)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:862)
at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:835)
at java.desktop/javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:784)
at java.desktop/javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1898)
at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:318)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:771)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:722)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:716)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:741)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)