java.lang.IllegalStateException: Peer does not exist while invoking the decreaseComponentCount() method
   at java.awt.Container.decreaseComponentCount(Container.java:4044)
   at java.awt.Component.removeNotify(Component.java:6996)
   at java.awt.Container.removeNotify(Container.java:2820)
   at javax.swing.JComponent.removeNotify(JComponent.java:4767)
   at javax.swing.AbstractButton.removeNotify(AbstractButton.java:1033)
   at java.awt.Container.removeNotify(Container.java:2804)
   at javax.swing.JComponent.removeNotify(JComponent.java:4767)
   at java.awt.Container.removeNotify(Container.java:2804)
   at javax.swing.JComponent.removeNotify(JComponent.java:4767)
   at java.awt.Container.remove(Container.java:1204)
   at javax.swing.JLayeredPane.remove(JLayeredPane.java:246)
   at java.awt.Container.remove(Container.java:1262)
   at javax.swing.PopupFactory$ContainerPopup.hide(PopupFactory.java:518)
   at javax.swing.PopupFactory$LightWeightPopup.hide(PopupFactory.java:735)
   at javax.swing.JPopupMenu.setVisible(JPopupMenu.java:796)
   at javax.swing.JMenu.setPopupMenuVisible(JMenu.java:347)
   at org.openide.awt.MenuBar$LazyMenu.setPopupMenuVisible(MenuBar.java:684)
   at javax.swing.JPopupMenu.menuSelectionChanged(JPopupMenu.java:1480)
   at javax.swing.MenuSelectionManager.setSelectedPath(MenuSelectionManager.java:119)
   at javax.swing.plaf.basic.BasicMenuUI$Handler.mouseEntered(BasicMenuUI.java:526)
   at javax.swing.plaf.basic.BasicMenuUI$MouseInputHandler.mouseEntered(BasicMenuUI.java:364)
   at com.sun.java.swing.plaf.windows.WindowsMenuUI$WindowsMouseInputHandler.mouseEntered(WindowsMenuUI.java:255)
   at java.awt.Component.processMouseEvent(Component.java:6534)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
   at java.awt.Component.processEvent(Component.java:6290)
   at java.awt.Container.processEvent(Container.java:2234)
   at java.awt.Component.dispatchEventImpl(Component.java:4881)
   at java.awt.Container.dispatchEventImpl(Container.java:2292)
   at java.awt.Component.dispatchEvent(Component.java:4703)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4898)
   at java.awt.LightweightDispatcher.retargetMouseEnterExit(LightweightDispatcher.java:4686)
   at java.awt.LightweightDispatcher.trackMouseEnterExit(LightweightDispatcher.java:4665)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4514)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4462)
   at java.awt.Container.dispatchEventImpl(Container.java:2278)
   at java.awt.Window.dispatchEventImpl(Window.java:2750)
   at java.awt.Component.dispatchEvent(Component.java:4703)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:751)
   at java.awt.EventQueue.access$500(EventQueue.java:97)
   at java.awt.EventQueue$3.run(EventQueue.java:702)
   at java.awt.EventQueue$3.run(EventQueue.java:696)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:86)
   at java.awt.EventQueue$4.run(EventQueue.java:724)
   at java.awt.EventQueue$4.run(EventQueue.java:722)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:721)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:159)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)