java.lang.Exception: Stack trace
	at java.lang.Thread.dumpStack(Thread.java:1158)
	at org.openide.actions.UndoAction.updateStatus(Unknown Source)
	at org.openide.actions.UndoAction$Listener.propertyChange(Unknown Source)
	at org.openide.util.WeakListenerImpl$PropertyChange.propertyChange(WeakListenerImpl.java:131)
	at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:333)
	at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:270)
	at org.netbeans.core.windows.RegistryImpl.tryFireChanges(RegistryImpl.java:234)
	at org.netbeans.core.windows.RegistryImpl.selectedNodesChanged(RegistryImpl.java:188)
	at org.netbeans.core.windows.WindowManagerImpl.notifyRegistrySelectedNodesChanged(WindowManagerImpl.java:897)
	at org.netbeans.core.windows.WindowManagerImpl.topComponentActivatedNodesChanged(WindowManagerImpl.java:1018)
	at org.openide.windows.TopComponent.setActivatedNodes(TopComponent.java:222)
	at org.netbeans.modules.java.JavaEditor$JavaEditorComponent$1$2.run(JavaEditor.java:1200)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
	at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:234)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
java.lang.Exception: Stack trace
	at java.lang.Thread.dumpStack(Thread.java:1158)
	at org.netbeans.modules.java.JavaEditor$JavaEditorComponent$3.caretUpdate(JavaEditor.java:1334)
	at javax.swing.text.JTextComponent.fireCaretUpdate(JTextComponent.java:367)
	at javax.swing.text.JTextComponent$MutableCaretEvent.fire(JTextComponent.java:3232)
	at javax.swing.text.JTextComponent$MutableCaretEvent.stateChanged(JTextComponent.java:3254)
	at org.netbeans.editor.BaseCaret$3.run(BaseCaret.java:598)
	at org.netbeans.editor.Utilities.runInEventDispatchThread(Utilities.java:902)
	at org.netbeans.editor.BaseCaret.fireStateChanged(BaseCaret.java:590)
	at org.netbeans.editor.BaseCaret.modifiedUpdate(BaseCaret.java:952)
	at org.netbeans.editor.BaseCaret.atomicUnlock(BaseCaret.java:966)
	at org.netbeans.editor.BaseDocument.fireAtomicUnlock(BaseDocument.java:1135)
	at org.netbeans.editor.BaseDocument.atomicUnlockImpl(BaseDocument.java:1081)
	at org.netbeans.editor.BaseDocument.atomicUnlock(BaseDocument.java:1070)
	at org.netbeans.editor.BaseDocument.runAtomicAsUser(BaseDocument.java:920)
	at org.netbeans.editor.GuardedDocument.runAtomic(GuardedDocument.java:217)
	at org.openide.text.CloneableEditorSupport$CESUndoRedoManager$RenderUndo.<init>(CloneableEditorSupport.java:2303)
	at org.openide.text.CloneableEditorSupport$CESUndoRedoManager$RenderUndo.<init>(CloneableEditorSupport.java:2295)
	at org.openide.text.CloneableEditorSupport$CESUndoRedoManager.canUndo(CloneableEditorSupport.java:2244)
	at org.openide.actions.UndoAction$1.run(Unknown Source)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
	at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:234)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)