language server throws NPE

[martinlippert]

Not sure when exactly this exception was thrown by the language server, but it appears in the logs. Maybe also happened while manually changing the spring boot parent pom version in the pom.xml file.

12:04:56.445 [pool-2-thread-5] ERROR o.s.i.v.b.j.c.JdtCodeActionHandler - 
java.lang.NullPointerException: Cannot invoke "org.springframework.ide.vscode.commons.languageserver.reconcile.ProblemType.getCategory()" because "problem" is null
	at org.springframework.ide.vscode.boot.app.BootDiagnosticSeverityProvider.getDiagnosticSeverity(BootDiagnosticSeverityProvider.java:30)
	at org.springframework.ide.vscode.boot.java.reconcilers.ReconcileProblemCodeActionProvider.createVisitor(ReconcileProblemCodeActionProvider.java:83)
	at org.springframework.ide.vscode.boot.java.codeaction.JdtCodeActionHandler.lambda$1(JdtCodeActionHandler.java:100)
	at org.springframework.ide.vscode.boot.java.utils.CompilationUnitCache.withCompilationUnit(CompilationUnitCache.java:239)
	at org.springframework.ide.vscode.boot.java.codeaction.JdtCodeActionHandler.handle(JdtCodeActionHandler.java:92)
	at org.springframework.ide.vscode.boot.java.handlers.BootJavaCodeActionProvider.lambda$0(BootJavaCodeActionProvider.java:52)
	at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:273)
	at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133)
	at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1939)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
	at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)
	at org.springframework.ide.vscode.boot.java.handlers.BootJavaCodeActionProvider.handle(BootJavaCodeActionProvider.java:57)
	at org.springframework.ide.vscode.commons.languageserver.composable.CompositeLanguageServerComponents$3.lambda$2(CompositeLanguageServerComponents.java:147)
	at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:273)
	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1708)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
	at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)
	at org.springframework.ide.vscode.commons.languageserver.composable.CompositeLanguageServerComponents$3.handle(CompositeLanguageServerComponents.java:148)
	at org.springframework.ide.vscode.commons.languageserver.util.SimpleTextDocumentService.computeCodeActions(SimpleTextDocumentService.java:539)
	at org.springframework.ide.vscode.commons.languageserver.util.SimpleTextDocumentService.lambda$19(SimpleTextDocumentService.java:585)
	at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:646)
	at java.base/java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:482)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
	at java.base/java.lang.Thread.run(Thread.java:1583)