java.lang.NullPointerException
   at org.netbeans.modules.uml.drawingarea.actions.SceneAcceptAction.<init>(SceneAcceptAction.java:98)
   at org.netbeans.modules.uml.drawingarea.UMLDiagramTopComponent$6.propertyChange(UMLDiagramTopComponent.java:750)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
   at org.netbeans.spi.palette.PaletteController$1.propertyChange(PaletteController.java:188)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
   at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
   at org.netbeans.modules.palette.DefaultModel.setSelectedItem(DefaultModel.java:116)
   at org.netbeans.modules.palette.ui.PalettePanel.select(PalettePanel.java:282)
   at org.netbeans.modules.palette.ui.CategoryDescriptor$2.valueChanged(CategoryDescriptor.java:114)
   at javax.swing.JList.fireSelectionValueChanged(JList.java:1765)
   at javax.swing.JList$ListSelectionHandler.valueChanged(JList.java:1779)
   at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:167)
   at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:147)
   at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:194)
   at javax.swing.DefaultListSelectionModel.changeSelection(DefaultListSelectionModel.java:388)
   at javax.swing.DefaultListSelectionModel.changeSelection(DefaultListSelectionModel.java:398)
   at javax.swing.DefaultListSelectionModel.setSelectionInterval(DefaultListSelectionModel.java:442)
   at javax.swing.JList.setSelectionInterval(JList.java:2035)
   at javax.swing.plaf.basic.BasicListUI$Handler.adjustSelection(BasicListUI.java:2731)
   at javax.swing.plaf.basic.BasicListUI$Handler.mousePressed(BasicListUI.java:2687)
   at javax.swing.plaf.basic.BasicListUI$MouseInputHandler.mousePressed(BasicListUI.java:1502)
   at org.netbeans.modules.palette.ui.CategoryList$CategoryListUI$ListMouseInputHandler.mousePressed(CategoryList.java:458)
   at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:263)
   at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:262)
   at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:262)
   at java.awt.Component.processMouseEvent(Component.java:6260)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
   at java.awt.Component.processEvent(Component.java:6028)
   at java.awt.Container.processEvent(Container.java:2041)
   at java.awt.Component.dispatchEventImpl(Component.java:4630)
   at java.awt.Container.dispatchEventImpl(Container.java:2099)
   at java.awt.Component.dispatchEvent(Component.java:4460)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4574)
   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:2475)
   at java.awt.Component.dispatchEvent(Component.java:4460)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:125)
   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)