java.lang.NullPointerException
        at org.netbeans.modules.editor.hints.AnnotationHolder.removeUpdate(AnnotationHolder.java:410)
        at org.netbeans.lib.editor.util.swing.PriorityDocumentListenerList.removeUpdate(PriorityDocumentListenerList.java:99)
        at javax.swing.text.AbstractDocument.fireRemoveUpdate(AbstractDocument.java:260)
        at org.netbeans.editor.BaseDocument.fireRemoveUpdate(BaseDocument.java:1626)
        at org.netbeans.editor.BaseDocument.remove(BaseDocument.java:925)
        at org.netbeans.editor.BaseKit$DeleteCharAction$1.run(BaseKit.java:1535)
        at org.netbeans.editor.GuardedDocument.runAtomicAsUser(GuardedDocument.java:357)
        at org.netbeans.editor.BaseKit$DeleteCharAction.actionPerformed(BaseKit.java:1521)
        at org.netbeans.modules.editor.java.JavaKit$JavaDeleteCharAction.actionPerformed(JavaKit.java:726)
        at org.netbeans.editor.BaseAction.actionPerformed(BaseAction.java:336)
        at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1658)
        at javax.swing.JComponent.processKeyBinding(JComponent.java:2851)
        at javax.swing.JComponent.processKeyBindings(JComponent.java:2886)
        at javax.swing.JComponent.processKeyEvent(JComponent.java:2814)
        at java.awt.Component.processEvent(Component.java:5885)
        at java.awt.Container.processEvent(Container.java:2105)
        at java.awt.Component.dispatchEventImpl(Component.java:4469)
        at java.awt.Container.dispatchEventImpl(Container.java:2163)
        at java.awt.Component.dispatchEvent(Component.java:4295)
        at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1881)
        at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:749)
        at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1025)
        at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:892)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:713)
        at java.awt.Component.dispatchEventImpl(Component.java:4339)
        at java.awt.Container.dispatchEventImpl(Container.java:2163)
        at java.awt.Window.dispatchEventImpl(Window.java:2478)
        at java.awt.Component.dispatchEvent(Component.java:4295)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:604)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:125)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:275)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:200)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:185)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:177)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:138)