NPE in profiler trying to display thread dump

[jglick]

Without this patch, opening a particular 16Gb heap dump I have (taken from Java 21) and clicking on the hyperlink to show threads fails with

java.lang.NullPointerException: Cannot invoke "java.lang.Boolean.booleanValue()" because "daemon" is null
	at org.netbeans.modules.profiler.heapwalk.OverviewController.getStackTrace(OverviewController.java:467)
	at org.netbeans.modules.profiler.heapwalk.OverviewController.computeThreads(OverviewController.java:277)
	at org.netbeans.modules.profiler.heapwalk.ui.OverviewControllerUI$1.run(OverviewControllerUI.java:125)
	at …

Why the daemon field would not be present, I do not know.

With the patch, the threads (about 400) are displayed, although the GUI freezes for a couple minutes

"AWT-EventQueue-0" #39 [54712] prio=6 os_prio=0 cpu=93980.19ms elapsed=119.05s tid=0x00007921680cb860 nid=54712 runnable  [0x0000792189dfc000]
   java.lang.Thread.State: RUNNABLE
	at sun.text.RuleBasedBreakIterator.handleNext(java.base@21.0.10/RuleBasedBreakIterator.java:940)
	at sun.text.RuleBasedBreakIterator.previous(java.base@21.0.10/RuleBasedBreakIterator.java:639)
	at sun.text.RuleBasedBreakIterator.preceding(java.base@21.0.10/RuleBasedBreakIterator.java:792)
	at javax.swing.text.GlyphView.getBreakSpot(java.desktop@21.0.10/GlyphView.java:792)
	at javax.swing.text.GlyphView.getBreakWeight(java.desktop@21.0.10/GlyphView.java:717)
	at javax.swing.text.html.InlineView.getBreakWeight(java.desktop@21.0.10/InlineView.java:150)
	at javax.swing.text.FlowView$LogicalView.getPreferredSpan(java.desktop@21.0.10/FlowView.java:754)
	at javax.swing.text.FlowView.calculateMinorAxisRequirements(java.desktop@21.0.10/FlowView.java:241)
	at javax.swing.text.ParagraphView.calculateMinorAxisRequirements(java.desktop@21.0.10/ParagraphView.java:709)
	at javax.swing.text.html.ParagraphView.calculateMinorAxisRequirements(java.desktop@21.0.10/ParagraphView.java:162)
	at javax.swing.text.BoxView.checkRequests(java.desktop@21.0.10/BoxView.java:936)
	at javax.swing.text.BoxView.getPreferredSpan(java.desktop@21.0.10/BoxView.java:546)
	at javax.swing.text.html.ParagraphView.getPreferredSpan(java.desktop@21.0.10/ParagraphView.java:258)
	at javax.swing.text.html.LineView.getMinimumSpan(java.desktop@21.0.10/LineView.java:74)
	at javax.swing.text.BoxView.calculateMinorAxisRequirements(java.desktop@21.0.10/BoxView.java:904)
	at javax.swing.text.html.BlockView.calculateMinorAxisRequirements(java.desktop@21.0.10/BlockView.java:146)
	at javax.swing.text.BoxView.checkRequests(java.desktop@21.0.10/BoxView.java:936)
	at javax.swing.text.BoxView.getMinimumSpan(java.desktop@21.0.10/BoxView.java:569)
	at javax.swing.text.html.BlockView.getMinimumSpan(java.desktop@21.0.10/BlockView.java:378)
	at javax.swing.text.BoxView.calculateMinorAxisRequirements(java.desktop@21.0.10/BoxView.java:904)
	at javax.swing.text.html.BlockView.calculateMinorAxisRequirements(java.desktop@21.0.10/BlockView.java:146)
	at javax.swing.text.BoxView.checkRequests(java.desktop@21.0.10/BoxView.java:936)
	at javax.swing.text.BoxView.getMinimumSpan(java.desktop@21.0.10/BoxView.java:569)
	at javax.swing.text.html.BlockView.getMinimumSpan(java.desktop@21.0.10/BlockView.java:378)
	at javax.swing.text.BoxView.calculateMinorAxisRequirements(java.desktop@21.0.10/BoxView.java:904)
	at javax.swing.text.html.BlockView.calculateMinorAxisRequirements(java.desktop@21.0.10/BlockView.java:146)
	at javax.swing.text.BoxView.checkRequests(java.desktop@21.0.10/BoxView.java:936)
	at javax.swing.text.BoxView.setSpanOnAxis(java.desktop@21.0.10/BoxView.java:344)
	at javax.swing.text.BoxView.layout(java.desktop@21.0.10/BoxView.java:709)
	at javax.swing.text.BoxView.setSize(java.desktop@21.0.10/BoxView.java:398)
	at javax.swing.plaf.basic.BasicTextUI$RootView.setSize(java.desktop@21.0.10/BasicTextUI.java:1839)
	at javax.swing.plaf.basic.BasicTextUI.getPreferredSize(java.desktop@21.0.10/BasicTextUI.java:959)
	at com.formdev.flatlaf.ui.FlatEditorPaneUI.getPreferredSize(FlatEditorPaneUI.java:223)
	at javax.swing.JComponent.getPreferredSize(java.desktop@21.0.10/JComponent.java:1734)
	at javax.swing.JEditorPane.getPreferredSize(java.desktop@21.0.10/JEditorPane.java:1392)
	at org.netbeans.lib.profiler.ui.components.HTMLTextArea.getPreferredSize(HTMLTextArea.java:654)
	at javax.swing.ScrollPaneLayout.layoutContainer(java.desktop@21.0.10/ScrollPaneLayout.java:799)
	at com.formdev.flatlaf.ui.FlatScrollPaneUI$FlatScrollPaneLayout.layoutContainer(FlatScrollPaneUI.java:563)
	at java.awt.Container.layout(java.desktop@21.0.10/Container.java:1541)
	at java.awt.Container.doLayout(java.desktop@21.0.10/Container.java:1530)
	at java.awt.Container.validateTree(java.desktop@21.0.10/Container.java:1725)
	at java.awt.Container.validate(java.desktop@21.0.10/Container.java:1660)
	- locked <0x000000041a4b0208> (a java.awt.Component$AWTTreeLock)
	at javax.swing.RepaintManager$3.run(java.desktop@21.0.10/RepaintManager.java:757)
	at …

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[mbien]

cool!