java.lang.NullPointerException: iconBase attribute not specified
   at org.netbeans.core.spi.multiview.MultiViewFactory$MapMVD.get(MultiViewFactory.java:379)
   at org.netbeans.core.spi.multiview.MultiViewFactory$MapMVD.getIcon(MultiViewFactory.java:400)
   at org.netbeans.core.multiview.MultiViewPeer.showCurrentElement(MultiViewPeer.java:359)
   at org.netbeans.core.multiview.MultiViewPeer.showCurrentElement(MultiViewPeer.java:343)
   at org.netbeans.core.multiview.MultiViewPeer$SelectionListener.selectionChanged(MultiViewPeer.java:741)
   at org.netbeans.core.multiview.MultiViewModel.fireSelectionChanged(MultiViewModel.java:246)
   at org.netbeans.core.multiview.MultiViewModel.setActiveDescription(MultiViewModel.java:118)
   at org.netbeans.core.multiview.MultiViewModel$BtnGroup.setSelected(MultiViewModel.java:296)
   at javax.swing.JToggleButton$ToggleButtonModel.setSelected(JToggleButton.java:237)
   at javax.swing.ButtonGroup.setSelected(ButtonGroup.java:147)
   at org.netbeans.core.multiview.MultiViewModel$BtnGroup.setSelected(MultiViewModel.java:292)
   at org.netbeans.core.multiview.TabsComponent$ButtonMouseListener.mousePressed(TabsComponent.java:449)
   at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:263)
   at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:262)
   at java.awt.Component.processMouseEvent(Component.java:6285)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
   at java.awt.Component.processEvent(Component.java:6053)
   at java.awt.Container.processEvent(Container.java:2041)
   at java.awt.Component.dispatchEventImpl(Component.java:4651)
   at java.awt.Container.dispatchEventImpl(Container.java:2099)
   at java.awt.Component.dispatchEvent(Component.java:4481)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4577)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4235)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4168)
   at java.awt.Container.dispatchEventImpl(Container.java:2085)
   at java.awt.Window.dispatchEventImpl(Window.java:2478)
   at java.awt.Component.dispatchEvent(Component.java:4481)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:643)
   at java.awt.EventQueue.access$000(EventQueue.java:84)
   at java.awt.EventQueue$1.run(EventQueue.java:602)
   at java.awt.EventQueue$1.run(EventQueue.java:600)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
   at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
   at java.awt.EventQueue$2.run(EventQueue.java:616)
   at java.awt.EventQueue$2.run(EventQueue.java:614)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:613)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:162)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)