[Bug swing/29566] New: NPEs from JTree repainting

[hendrich at informatik dot uni-hamburg dot de]

Hello Roman,

here are two more NPEs resulting from JTree repainting. I got these
while running a slide-show in Niffler under rather high system load
(heap memory almost exhausted, nominal 30 msec pause between images, 
both tree and image canvas visible). Classpath cvs 2006.10.20 with
jamvm on Linux x86.

This might well be a result of the high system load with lots of
garbage-collection. Still, it shouldn't happen, and might be worth 
checking:


Exception during event dispatch:
java.lang.NullPointerException
   at javax.swing.plaf.basic.BasicTreeUI.isLastChild(BasicTreeUI.java:1623)
   at javax.swing.plaf.basic.BasicTreeUI.paint(BasicTreeUI.java:1572)
   at javax.swing.plaf.metal.MetalTreeUI.paint(MetalTreeUI.java:248)
   at javax.swing.plaf.ComponentUI.update(ComponentUI.java:193)
   at javax.swing.JComponent.paintComponent(JComponent.java:2069)
   at javax.swing.JComponent.paint(JComponent.java:1834)
   at javax.swing.JViewport.paintSimple(JViewport.java:794)
   at javax.swing.JViewport.paintBackingStore(JViewport.java:850)
   at javax.swing.JViewport.paint(JViewport.java:495)
   at javax.swing.JComponent.paintChildren(JComponent.java:1969)
   at javax.swing.JComponent.paint(JComponent.java:1837)
   at javax.swing.JComponent.paintDoubleBuffered(JComponent.java:2349)
   at javax.swing.JComponent.paintImmediately2(JComponent.java:2266)
   at javax.swing.JComponent.paintImmediately(JComponent.java:2105)
   at javax.swing.JComponent.paintImmediately(JComponent.java:2131)
   at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:594)
   at javax.swing.RepaintManager$RepaintWorker.run(RepaintManager.java:170)
   at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:200)
   at
javax.swing.RepaintManager$RepaintWorkerEvent.dispatch(RepaintManager.java:114)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:609)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:85)




Exception during event dispatch:
java.lang.NullPointerException
   at javax.swing.JComponent.paintDoubleBuffered(JComponent.java:2332)
   at javax.swing.JComponent.paint(JComponent.java:1794)
   at
javax.swing.tree.DefaultTreeCellRenderer.paint(DefaultTreeCellRenderer.java:532)
   at javax.swing.CellRendererPane.paintComponent(CellRendererPane.java:189)
   at javax.swing.CellRendererPane.paintComponent(CellRendererPane.java:219)
   at javax.swing.CellRendererPane.paintComponent(CellRendererPane.java:237)
   at javax.swing.plaf.basic.BasicTreeUI.paintRow(BasicTreeUI.java:3892)
   at javax.swing.plaf.basic.BasicTreeUI.paint(BasicTreeUI.java:1603)
   at javax.swing.plaf.metal.MetalTreeUI.paint(MetalTreeUI.java:248)
   at javax.swing.plaf.ComponentUI.update(ComponentUI.java:193)
   at javax.swing.JComponent.paintComponent(JComponent.java:2069)
   at javax.swing.JComponent.paint(JComponent.java:1834)
   at javax.swing.JViewport.paintSimple(JViewport.java:794)
   at javax.swing.JViewport.paintBackingStore(JViewport.java:861)
   at javax.swing.JViewport.paint(JViewport.java:495)
   at javax.swing.JComponent.paintDoubleBuffered(JComponent.java:2349)
   at javax.swing.JComponent.paintImmediately2(JComponent.java:2266)
   at javax.swing.JComponent.paintImmediately(JComponent.java:2105)
   at javax.swing.JComponent.paintImmediately(JComponent.java:2131)
   at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:594)
   at javax.swing.RepaintManager$RepaintWorker.run(RepaintManager.java:170)
   at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:200)
   at
javax.swing.RepaintManager$RepaintWorkerEvent.dispatch(RepaintManager.java:114)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:609)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:85)


-- 
           Summary: NPEs from JTree repainting
           Product: classpath
           Version: 0.93
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: swing
        AssignedTo: roman at kennke dot org
        ReportedBy: hendrich at informatik dot uni-hamburg dot de


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29566