No auto-completion, no marking of compilation errors, etc.

I've done Clean Java Language Server Workspace, activated the "heavyweight mode" and waited for Java: Ready, but the extension still barely offers any support. Stack traces from the logs:

[Error - 11:33:40 AM] Request textDocument/codeAction failed.
  Message: Internal error.
  Code: -32603 
java.util.concurrent.CompletionException: java.lang.NullPointerException: Cannot invoke "org.eclipse.jdt.core.IMethod.getCompilationUnit()" because "iMethod" is null
	at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture.completeThrowable(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture$Completion.exec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.scan(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(Unknown Source)
Caused by: java.lang.NullPointerException: Cannot invoke "org.eclipse.jdt.core.IMethod.getCompilationUnit()" because "iMethod" is null
	at org.eclipse.jdt.internal.corext.refactoring.code.makestatic.InitialConditionsChecker.checkSourceAvailable(InitialConditionsChecker.java:181)
	at org.eclipse.jdt.internal.corext.refactoring.code.MakeStaticRefactoring.checkInitialConditions(MakeStaticRefactoring.java:127)
	at org.eclipse.jdt.ls.core.internal.corrections.RefactorProcessor.getMakeMethodStaticRefactoringProposal(RefactorProcessor.java:1189)
	at org.eclipse.jdt.ls.core.internal.corrections.RefactorProcessor.getProposals(RefactorProcessor.java:228)
	at org.eclipse.jdt.ls.core.internal.handlers.CodeActionHandler.getCodeActionCommands(CodeActionHandler.java:221)
	at org.eclipse.jdt.ls.core.internal.handlers.JDTLanguageServer.lambda$15(JDTLanguageServer.java:775)
	at org.eclipse.jdt.ls.core.internal.BaseJDTLanguageServer.lambda$0(BaseJDTLanguageServer.java:87)
	... 7 more

java.util.concurrent.CompletionException: java.lang.ArrayIndexOutOfBoundsException: Index -1 out of bounds for length 1
	at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture.completeThrowable(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture$Completion.exec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.scan(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(Unknown Source)
Caused by: java.lang.ArrayIndexOutOfBoundsException: Index -1 out of bounds for length 1
	at org.eclipse.jdt.internal.corext.fix.AddMissingMethodDeclarationFixCore$AddMissingMethodDeclarationProposalOperation.rewriteAST(AddMissingMethodDeclarationFixCore.java:241)
	at org.eclipse.jdt.internal.corext.fix.CompilationUnitRewriteOperationsFixCore.createChange(CompilationUnitRewriteOperationsFixCore.java:123)
	at org.eclipse.jdt.ls.core.internal.text.correction.QuickAssistProcessor.getAddMissingMethodDeclarationProposal(QuickAssistProcessor.java:1459)
	at org.eclipse.jdt.ls.core.internal.text.correction.QuickAssistProcessor.getAssists(QuickAssistProcessor.java:237)
	at org.eclipse.jdt.ls.core.internal.handlers.CodeActionHandler.getCodeActionCommands(CodeActionHandler.java:233)
	at org.eclipse.jdt.ls.core.internal.handlers.JDTLanguageServer.lambda$15(JDTLanguageServer.java:775)
	at org.eclipse.jdt.ls.core.internal.BaseJDTLanguageServer.lambda$0(BaseJDTLanguageServer.java:87)
	... 7 more

SEVERE: Internal error: java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
java.util.concurrent.CompletionException: java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
	at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture.completeThrowable(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture$Completion.exec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.scan(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(Unknown Source)
Caused by: java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
	at java.base/jdk.internal.util.Preconditions.outOfBounds(Unknown Source)
	at java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Unknown Source)
	at java.base/jdk.internal.util.Preconditions.checkIndex(Unknown Source)
	at java.base/java.util.Objects.checkIndex(Unknown Source)
	at java.base/java.util.ArrayList.get(Unknown Source)
	at org.eclipse.jdt.ls.core.internal.text.correction.QuickAssistProcessor.getTryWithResourceProposals(QuickAssistProcessor.java:1014)
	at org.eclipse.jdt.ls.core.internal.text.correction.QuickAssistProcessor.getTryWithResourceProposals(QuickAssistProcessor.java:936)
	at org.eclipse.jdt.ls.core.internal.text.correction.QuickAssistProcessor.getAssists(QuickAssistProcessor.java:238)
	at org.eclipse.jdt.ls.core.internal.handlers.CodeActionHandler.getCodeActionCommands(CodeActionHandler.java:233)
	at org.eclipse.jdt.ls.core.internal.handlers.JDTLanguageServer.lambda$15(JDTLanguageServer.java:775)
	at org.eclipse.jdt.ls.core.internal.BaseJDTLanguageServer.lambda$0(BaseJDTLanguageServer.java:87)
	... 7 more

pre-release extension version 1.43.2025061908

Version: 1.101.1 (user setup)
Commit: 18e3a1ec544e6907be1e944a94c496e302073435
Date: 2025-06-18T13:35:12.605Z
Electron: 35.5.1
ElectronBuildId: 11727614
Chromium: 134.0.6998.205
Node.js: 22.15.1
V8: 13.4.114.21-electron.0
OS: Windows_NT x64 10.0.22631

Commencez par les chemins de CodeActionHandler signalés et les trois stack traces, en suivant RefactorProcessor, QuickAssistProcessor et JDTLanguageServer. Reproduisez les échecs dans les versions indiquées de VS Code et de l’extension, puis déterminez les flux d’actions de code concernés. Le travail est considéré comme terminé lorsque ces erreurs internes sont résolues et que la prise en charge de la complétion et des erreurs de compilation fonctionne dans la configuration signalée.