java.lang.Exception: Stack trace
        at java.lang.Thread.dumpStack(Thread.java:1064)
        at org.netbeans.editor.EditorUI.uninstallUI(EditorUI.java:405)
        at org.netbeans.modules.editor.NbEditorUI.uninstallUI(NbEditorUI.java:136)
        at org.netbeans.editor.BaseTextUI.uninstallUI(BaseTextUI.java:253)
        at javax.swing.JComponent.setUI(JComponent.java:444)
        at javax.swing.text.JTextComponent.setUI(JTextComponent.java:287)
        at javax.swing.text.JTextComponent.updateUI(JTextComponent.java:297)
        at org.netbeans.editor.BaseKit.deinstall(BaseKit.java:521)
        at javax.swing.JEditorPane.setEditorKit(JEditorPane.java:940)
        at org.openide.text.CloneableEditor$1.run(CloneableEditor.java:138)
        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 org.netbeans.core.windows.services.NbPresenter.superShow(NbPresenter.java:798)
        at org.netbeans.core.windows.services.NbPresenter.doShow(NbPresenter.java:841)
        at org.netbeans.core.windows.services.NbPresenter.run(NbPresenter.java:829)
        at org.openide.util.Mutex.doEventAccess(Mutex.java:1044)
        at org.openide.util.Mutex.readAccess(Mutex.java:170)
        at org.netbeans.core.windows.services.NbPresenter.show(NbPresenter.java:814)
        at java.awt.Component.show(Component.java:1133)
        at java.awt.Component.setVisible(Component.java:1088)
        at org.netbeans.core.windows.services.DialogDisplayerImpl$1AWTQuery.showDialog(DialogDisplay
erImpl.java:154)
        at org.netbeans.core.windows.services.DialogDisplayerImpl.notify(DialogDisplayerImpl.java:16
9)
        at org.openide.text.CloneableEditorSupport.canClose(CloneableEditorSupport.java:945)
        at org.openide.text.DataEditorSupport.canClose(DataEditorSupport.java:234)
        at org.netbeans.modules.form.FormEditorSupport.access$1600(FormEditorSupport.java:47)
        at org.netbeans.modules.form.FormEditorSupport$CloseHandler.resolveCloseOperation(FormEditor
Support.java:1627)
        at org.netbeans.core.multiview.MultiViewPeer.canClose(MultiViewPeer.java:444)
        at org.netbeans.core.multiview.MultiViewCloneableTopComponent.canClose(MultiViewCloneableTop
Component.java:269)
        at org.netbeans.core.windows.Central.removeModeTopComponent(Central.java:706)
        at org.netbeans.core.windows.Central.userClosedTopComponent(Central.java:1536)
        at org.netbeans.core.windows.view.DefaultView.userClosedTopComponent(DefaultView.java:739)
        at org.netbeans.core.windows.view.ui.TabbedHandler.actionPerformed(TabbedHandler.java:293)
        at org.netbeans.swing.tabcontrol.TabbedContainer.postActionEvent(TabbedContainer.java:662)
        at org.netbeans.swing.tabcontrol.TabbedContainerUI.shouldPerformAction(TabbedContainerUI.jav
a:134)
        at org.netbeans.swing.tabcontrol.plaf.DefaultTabbedContainerUI.access$2600(DefaultTabbedCont
ainerUI.java:55)
        at org.netbeans.swing.tabcontrol.plaf.DefaultTabbedContainerUI$DisplayerActionListener.actio
nPerformed(DefaultTabbedContainerUI.java:1203)
        at org.netbeans.swing.tabcontrol.TabDisplayer.postActionEvent(TabDisplayer.java:506)
        at org.netbeans.swing.tabcontrol.TabDisplayerUI.shouldPerformAction(TabDisplayerUI.java:144)

        at org.netbeans.swing.tabcontrol.plaf.BasicTabDisplayerUI.access$1500(BasicTabDisplayerUI.ja
va:74)
        at org.netbeans.swing.tabcontrol.plaf.BasicTabDisplayerUI$BasicDisplayerMouseListener.perfor
mCommand(BasicTabDisplayerUI.java:688)
        at org.netbeans.swing.tabcontrol.plaf.BasicTabDisplayerUI$BasicDisplayerMouseListener.potent
ialCommand(BasicTabDisplayerUI.java:673)
        at org.netbeans.swing.tabcontrol.plaf.BasicTabDisplayerUI$BasicDisplayerMouseListener.mouseR
eleased(BasicTabDisplayerUI.java:721)
        at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:231)
        at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:231)
        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)