javax.swing.undo.CannotUndoException
   at javax.swing.undo.AbstractUndoableEdit.undo(AbstractUndoableEdit.java:110)
   at javax.swing.undo.CompoundEdit.undo(CompoundEdit.java:59)
   at org.openide.text.UndoRedoManager.undoSaveActions(UndoRedoManager.java:282)
   at org.openide.text.UndoRedoManager.beforeRedoAtSavepoint(UndoRedoManager.java:318)
   at org.openide.text.WrapUndoEdit.redo(WrapUndoEdit.java:114)
   at org.openide.awt.UndoRedo$Manager.redoTo(UndoRedo.java:293)
   at org.openide.awt.UndoRedo$Manager.redo(UndoRedo.java:263)
   at org.openide.text.UndoRedoManager.access$101(UndoRedoManager.java:98)
   at org.openide.text.UndoRedoManager$DocLockedRun.run(UndoRedoManager.java:654)
   at org.netbeans.editor.GuardedDocument.runAtomic(GuardedDocument.java:321)
   at org.openide.text.UndoRedoManager$DocLockedRun.<init>(UndoRedoManager.java:632)
   at org.openide.text.UndoRedoManager$DocLockedRun.<init>(UndoRedoManager.java:624)
   at org.openide.text.UndoRedoManager$DocLockedRun.<init>(UndoRedoManager.java:620)
   at org.openide.text.UndoRedoManager.redo(UndoRedoManager.java:428)
   at org.netbeans.core.multiview.MultiViewPeer$DelegateUndoRedo.redo(MultiViewPeer.java:954)
   at org.openide.actions.UndoRedoAction.actionPerformed(UndoRedoAction.java:230)
   at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
   at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
   at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
   at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
   at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
   at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:290)
   at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:289)
   at java.awt.Component.processMouseEvent(Component.java:6505)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3320)
   at java.awt.Component.processEvent(Component.java:6270)
   at java.awt.Container.processEvent(Container.java:2229)
   at java.awt.Component.dispatchEventImpl(Component.java:4861)
   at java.awt.Container.dispatchEventImpl(Container.java:2287)
   at java.awt.Component.dispatchEvent(Component.java:4687)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4832)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4492)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4422)
   at java.awt.Container.dispatchEventImpl(Container.java:2273)
   at java.awt.Window.dispatchEventImpl(Window.java:2719)
   at java.awt.Component.dispatchEvent(Component.java:4687)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735)
   at java.awt.EventQueue.access$200(EventQueue.java:103)
   at java.awt.EventQueue$3.run(EventQueue.java:694)
   at java.awt.EventQueue$3.run(EventQueue.java:692)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
   at java.awt.EventQueue$4.run(EventQueue.java:708)
   at java.awt.EventQueue$4.run(EventQueue.java:706)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:159)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)