NullPointerException

Problem
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Exception in thread "AWT-EventQueue-1" java.lang.NullPointerException
at it.codegen.tbx.reservationclient.presentation.treeutils.BookingTreeRenderer.getTreeCellRendererComponent(BookingTreeRenderer.java:150)
at javax.swing.plaf.basic.BasicTreeUI.paintRow(BasicTreeUI.java:1413)
at javax.swing.plaf.basic.BasicTreeUI.paint(BasicTreeUI.java:1203)
at javax.swing.plaf.metal.MetalTreeUI.paint(MetalTreeUI.java:152)
at javax.swing.plaf.ComponentUI.update(ComponentUI.java:142)
at javax.swing.JComponent.paintComponent(JComponent.java:742)
at javax.swing.JComponent.paint(JComponent.java:1005)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JViewport.paint(JViewport.java:728)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JSplitPane.paintChildren(JSplitPane.java:1021)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JLayeredPane.paint(JLayeredPane.java:559)
at javax.swing.JComponent.paintChildren(JComponent.java:842)
at javax.swing.JComponent.paint(JComponent.java:1014)
at javax.swing.JComponent.paintWithOffscreenBuffer(JComponent.java:4963)
at javax.swing.JComponent.paintDoubleBuffered(JComponent.java:4916)
at javax.swing.JComponent._paintImmediately(JComponent.java:4859)
at javax.swing.JComponent.paintImmediately(JComponent.java:4666)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:451)
at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:114)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
at it.codegen.presentation.CGEventQueue.dispatchEvent(CGEventQueue.java:23)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
Return true...
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)

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Answer

Here the issue is one object returns a null value
In here node object returns null and getData() makes a NUllpointerException

to avoid this
make sure all the values are set before get those
in other words setters are well called before the getters