Please look at the attached code. When clicking on the red rectangle (mouse handler changes the scale of the red rectangle), the application throws this exception:

Unexpected exception caught in MasterTimer.timePulse():
java.lang.NullPointerException
        at com.sun.scenario.scenegraph.CacheFilter.render(CacheFilter.java:61)
        at com.sun.scenario.scenegraph.SGNode.renderCached(SGNode.java:1022)
        at com.sun.scenario.scenegraph.SGNode.doRender(SGNode.java:838)
        at com.sun.scenario.scenegraph.SGNode.render(SGNode.java:822)
        at com.sun.scenario.scenegraph.SGGroup.renderContent(SGGroup.java:325)
        at com.sun.scenario.scenegraph.SGNode.renderRectClip(SGNode.java:950)
        at com.sun.scenario.scenegraph.SGNode.renderClip(SGNode.java:855)
        at com.sun.scenario.scenegraph.SGNode.doRender(SGNode.java:834)
        at com.sun.scenario.scenegraph.SGNode.render(SGNode.java:822)
        at com.sun.scenario.scenegraph.SGGroup.renderContent(SGGroup.java:325)
        at com.sun.scenario.scenegraph.SGNode.doRender(SGNode.java:845)
        at com.sun.scenario.scenegraph.SGNode.render(SGNode.java:800)
        at com.sun.scenario.scenegraph.SGGroup.renderContent(SGGroup.java:325)
        at com.sun.scenario.scenegraph.SGNode.doRender(SGNode.java:845)
        at com.sun.scenario.scenegraph.SGNode.render(SGNode.java:800)
        at com.sun.scenario.scenegraph.JSGPanel.paintComponent(JSGPanel.java:243)
        at javax.swing.JComponent.paint(JComponent.java:1027)
        at javax.swing.JComponent.paintChildren(JComponent.java:864)
        at javax.swing.JComponent.paint(JComponent.java:1036)
        at javax.swing.JLayeredPane.paint(JLayeredPane.java:564)
        at javax.swing.JComponent.paintChildren(JComponent.java:864)
        at javax.swing.JComponent.paint(JComponent.java:1036)
        at com.sun.javafx.tk.swing.WindowImpl$2$1.paint(WindowImpl.java:152)
        at javax.swing.JComponent._paintImmediately(JComponent.java:5096)
        at javax.swing.JComponent.paintImmediately(JComponent.java:4880)
        at javax.swing.JComponent.paintImmediately(JComponent.java:4892)
        at com.sun.scenario.scenegraph.JSGPanel.repaintDirtyRegions(JSGPanel.java:332)
        at com.sun.scenario.scenegraph.JSGPanelRepainter.repaintAll(JSGPanelRepainter.java:122)
        at com.sun.scenario.scenegraph.JSGPanelRepainter$FrameDisplay.run(JSGPanelRepainter.java:134)
        at com.sun.scenario.animation.AbstractMasterTimer.timePulseImpl(AbstractMasterTimer.java:397)
        at com.sun.scenario.animation.AbstractMasterTimer$MainLoop.run(AbstractMasterTimer.java:274)
        at com.sun.embeddedswing.EmbeddedEventQueue.doPulse(EmbeddedEventQueue.java:562)
        at com.sun.embeddedswing.EmbeddedEventQueue.access$000(EmbeddedEventQueue.java:74)
        at com.sun.embeddedswing.EmbeddedEventQueue$2.run(EmbeddedEventQueue.java:465)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:633)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)