Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException

[hemanth.balaji]

I am getting the following exception when I am running my Swing Application. But the program continues and does not terminate abruptly unlike general Exceptions

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.plaf.basic.BasicTreeUI.paintRow(BasicTreeUI.java:1399)
at javax.swing.plaf.basic.BasicTreeUI.paint(BasicTreeUI.java:1189)
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.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 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)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)

How do I avoid this exception. What would be the cause for such an exception

[javaAddict]

This is part of the stack trace:
BasicTreeUI.paintRow(BasicTreeUI.java:1399)
It means that at the file BasicTreeUI.java, you have an Exception at line 1399 (function paintRow). You are trying to use something that is null.

[hemanth.balaji]

This is part of the stack trace:
BasicTreeUI.paintRow(BasicTreeUI.java:1399)
It means that at the file BasicTreeUI.java, you have an Exception at line 1399 (function paintRow). You are trying to use something that is null.

Hi mate,
Yes From the stackTrace I got the point about BasicTreeUI being null. But the fact is its an internal code and I simply dont know why this is being Null. Its a Builtin java class which i did not touch

[javaAddict]

I cannot tell much without the code. But I know for sure that at the specific line there is something which is null and you use it

[Kallathiyan]

Hi,
This Exception is bcz an EventDispatch Thread runs in the java Background, try using swingWorker.invokeLater.

[harithay85]

how to use swingWorker.invokeLater() method
please tell me i am getting the same error when iam passing track id and submitting it
its passed to a download method.....on submission
but i am getting "awt-eventqueue-0 null pointer exception"

[JamesCherrill]

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