NullPointerException: Cannot invoke "org.netbeans.api.debugger.jpda.JPDADebugger.removePropertyChangeListener(String, java.beans.PropertyChangeListener)" because "this.debugger" is null

[entlicher]

Apache NetBeans version

Apache NetBeans 27

What happened

This is a transient issue in debugger tests:

java.lang.NullPointerException: Cannot invoke "org.netbeans.api.debugger.jpda.JPDADebugger.removePropertyChangeListener(String, java.beans.PropertyChangeListener)" because "this.debugger" is null
        at org.netbeans.modules.debugger.jpda.console.DebuggerOutput.destroy(DebuggerOutput.java:113)
        at org.netbeans.modules.debugger.jpda.console.DebuggerOutput.propertyChange(DebuggerOutput.java:274)
        at java.desktop/java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:343)
        at java.desktop/java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:336)
        at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.firePropertyChange(JPDADebuggerImpl.java:2253)
        at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.resume(JPDADebuggerImpl.java:1793)
        at org.netbeans.modules.debugger.jpda.actions.ContinueActionProvider.doAction(ContinueActionProvider.java:58)
        at org.netbeans.spi.debugger.ActionsProvider$ContextAware.doAction(ActionsProvider.java:234)
        at org.netbeans.api.debugger.ActionsManager.doAction(ActionsManager.java:152)
        at org.netbeans.api.debugger.jpda.JPDASupport.doContinue(JPDASupport.java:315)
        at org.netbeans.api.debugger.jpda.CallStackTest.testInstanceCallStackInfo(CallStackTest.java:140)
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
        at java.base/java.lang.reflect.Method.invoke(Method.java:580)
        at junit.framework.TestCase.runTest(TestCase.java:177)
        at org.netbeans.junit.NbTestCase.access$200(NbTestCase.java:84)
        at org.netbeans.junit.NbTestCase$2.doSomething(NbTestCase.java:489)
        at org.netbeans.junit.NbTestCase$1Guard.run(NbTestCase.java:410)

Language / Project Type / NetBeans Component

Java Debugger

How to reproduce

Run JPDA tests.

Did this work correctly in an earlier version?

No / Don't know

Operating System

Any

JDK

Any

Apache NetBeans packaging

Other

Anything else

No response

Are you willing to submit a pull request?

No

[scalyon]

I'm trying to use NB 28 for some C++ code and received a similar error when trying to use the debugger:

java.lang.NullPointerException: Cannot invoke "org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.addPropertyChangeListener(java.beans.PropertyChangeListener)" because "this.debugger" is null
	at org.netbeans.modules.debugger.jpda.ui.models.InlineValueComputerImpl.<init>(InlineValueComputerImpl.java:101)
	at org.netbeans.modules.debugger.jpda.ui.models.InlineValueComputerImpl$Init.sessionAdded(InlineValueComputerImpl.java:306)
[catch] at org.netbeans.api.debugger.DebuggerManager.fireSessionAdded(DebuggerManager.java:1324)
	at org.netbeans.api.debugger.DebuggerManager.addSession(DebuggerManager.java:1598)
	at org.netbeans.api.debugger.DebuggerManager.startDebugging(DebuggerManager.java:314)
	at org.netbeans.modules.cpplite.debugger.CPPLiteDebugger.startDebugging(CPPLiteDebugger.java:845)
	at org.netbeans.modules.cpplite.debugger.api.Debugger.startInDebugger(Debugger.java:43)
	at org.netbeans.modules.cpplite.project.ActionProviderImpl.lambda$invokeAction$4(ActionProviderImpl.java:88)
	at org.netbeans.api.extexecution.base.BaseExecutionService$2.call(BaseExecutionService.java:236)
	at org.netbeans.api.extexecution.base.BaseExecutionService$2.call(BaseExecutionService.java:212)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
	at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1403)
	at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:45)
	at org.openide.util.lookup.Lookups.executeWith(Lookups.java:287)
	at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2018)

[matthiasblaesing]

@scalyon you correctly identified an issue, but I don't see it relate to the origin issue (apart from the fact that is also in the debugger area). Please have a look at #9073 and lets continue to the discussion there.