java.lang.AssertionError: Scene.validate was not called after last change. Widget is not validated. See first Q/A at http://graph.netbeans.org/faq.html page.
        at org.netbeans.api.visual.widget.SceneComponent.processLocationOperator(SceneComponent.java:307)
        at org.netbeans.api.visual.widget.SceneComponent.processLocationOperator(SceneComponent.java:316)
        at org.netbeans.api.visual.widget.SceneComponent.processLocationOperator(SceneComponent.java:316)
        at org.netbeans.api.visual.widget.SceneComponent.processLocationOperator(SceneComponent.java:279)
        at org.netbeans.api.visual.widget.SceneComponent.mouseExited(SceneComponent.java:163)
        at java.awt.AWTEventMulticaster.mouseExited(AWTEventMulticaster.java:292)
        at java.awt.Component.processMouseEvent(Component.java:6047)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3265)
        at java.awt.Component.processEvent(Component.java:5806)
        at java.awt.Container.processEvent(Container.java:2058)
        at java.awt.Component.dispatchEventImpl(Component.java:4413)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4322)
        at java.awt.LightweightDispatcher.trackMouseEnterExit(LightweightDispatcher.java:4103)
        at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:3968)
        at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:3916)
        at java.awt.Container.dispatchEventImpl(Container.java:2102)
        at java.awt.Window.dispatchEventImpl(Window.java:2440)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)