java.lang.NullPointerException
        at org.netbeans.modules.editor.hints.AnnotationHolder.insertUpdate(AnnotationHolder.java:310)
        at org.netbeans.lib.editor.util.swing.PriorityDocumentListenerList.insertUpdate(PriorityDocumentListenerList.java:79)
        at javax.swing.text.AbstractDocument.fireInsertUpdate(AbstractDocument.java:185)
        at org.netbeans.editor.BaseDocument.fireInsertUpdate(BaseDocument.java:1623)
        at org.netbeans.editor.BaseDocument.insertString(BaseDocument.java:778)
        at org.netbeans.editor.ext.ExtKit$ToggleCommentAction.comment(ExtKit.java:982)
        at org.netbeans.editor.ext.ExtKit$ToggleCommentAction.access$500(ExtKit.java:894)
        at org.netbeans.editor.ext.ExtKit$ToggleCommentAction$1.run(ExtKit.java:946)
        at org.netbeans.editor.GuardedDocument.runAtomicAsUser(GuardedDocument.java:357)
        at org.netbeans.editor.ext.ExtKit$ToggleCommentAction.commentUncomment(ExtKit.java:924)
        at org.netbeans.editor.ext.ExtKit$ToggleCommentAction.actionPerformed(ExtKit.java:913)
        at org.netbeans.editor.BaseAction.actionPerformed(BaseAction.java:336)
        at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1636)
        at javax.swing.JComponent.processKeyBinding(JComponent.java:2849)
        at javax.swing.JComponent.processKeyBindings(JComponent.java:2884)
        at javax.swing.JComponent.processKeyEvent(JComponent.java:2812)
        at java.awt.Component.processEvent(Component.java:5818)
        at java.awt.Container.processEvent(Container.java:2058)
        at java.awt.Component.dispatchEventImpl(Component.java:4413)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1848)
        at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:697)
        at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:962)
        at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:834)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:661)
        at java.awt.Component.dispatchEventImpl(Component.java:4285)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Window.dispatchEventImpl(Window.java:2440)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:125)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)