NullPointerException in FlowView.changedUpdate()

[Mark Sintrel]

Here's the Java API code (javax.swing.text.FlowView) that gives me the NPE:

/**
     * Gives notification from the document that attributes were changed
     * in a location that this view is responsible for.
     *
     * @param changes the change information from the associated document
     * @param a the current allocation of the view
     * @param f the factory to use to rebuild if the view has children
     * @see View#changedUpdate
     */
    public void changedUpdate(DocumentEvent changes, Shape a, ViewFactory f) {
[B]layoutPool.changedUpdate(changes, a, f);[/B]
strategy.changedUpdate(this, changes, getInsideAllocation(a));
    }  

The line in bold above is line 264 which gives me the exception:

Exception occurred during event dispatching:
java.lang.NullPointerException
at javax.swing.text.FlowView.changedUpdate(FlowView.java:264)
at javax.swing.text.ParagraphView.changedUpdate(ParagraphView.java:680)
at javax.swing.text.View.forwardUpdateToView(View.java:1221)
at javax.swing.text.View.forwardUpdate(View.java:1192)
at javax.swing.text.BoxView.forwardUpdate(BoxView.java:222)
at javax.swing.text.View.changedUpdate(View.java:798)
at javax.swing.plaf.basic.BasicTextUI$RootView.changedUpdate(BasicTextUI.java:1515)
at javax.swing.plaf.basic.BasicTextUI$UpdateHandler.changedUpdate(BasicTextUI.java:1756)
at javax.swing.text.AbstractDocument.fireChangedUpdate(AbstractDocument.java:213)
at javax.swing.text.DefaultStyledDocument$ChangeUpdateRunnable.run(DefaultStyledDocument.java:2477)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:178)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:454)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:141)
at java.awt.Dialog$1.run(Dialog.java:540)
at java.awt.Dialog.show(Dialog.java:561)
at mypackage.dialogs.TemplateDialog.show(TemplateDialog.java:282)
at mypackage.program.initOpenTemplate(designondemand.java:574)
at mypackage.commands.cmdOpenTemplate.actionPerformed(cmdOpenTemplate.java:29)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1786)
at javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(AbstractButton.java:1839)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258)
at javax.swing.AbstractButton.doClick(AbstractButton.java:289)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1113)
at javax.swing.plaf.basic.BasicMenuItemUI$MouseInputHandler.mouseReleased(BasicMenuItemUI.java:943)
at java.awt.Component.processMouseEvent(Component.java:5100)
at java.awt.Component.processEvent(Component.java:4897)
at java.awt.Container.processEvent(Container.java:1569)
at java.awt.Component.dispatchEventImpl(Component.java:3615)
at java.awt.Container.dispatchEventImpl(Container.java:1627)
at java.awt.Component.dispatchEvent(Component.java:3477)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3483)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3198)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3128)
at java.awt.Container.dispatchEventImpl(Container.java:1613)
at java.awt.Window.dispatchEventImpl(Window.java:1606)
at java.awt.Component.dispatchEvent(Component.java:3477)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:456)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:145)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:137)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:100)

The exception occurs sometimes when I set a lot of paragraph attributes and character attributes on a DefaultStyledDocument (or at least that's where I think it happens, haven't been able to trace it to a specific source).

So I tried moving all code where I update the DefaultStyledDocument into SwingUtilities.invokeAndWait() but that didn't change anything.

Can anyone see what's happening here?