[javac][binding] NPE when trying to rename a local variable assignment.

[gayanper]

List<String> names = generateNames("A", "Z");

Try renaming the names, This to reproduce the statement must be in a overriden interface method which interface method doesn't have any documentation.

java.util.concurrent.CompletionException: java.lang.NullPointerException: Cannot read field "owner" because "this.variableSymbol" is null
    at java.base/java.util.concurrent.CompletableFuture.wrapInCompletionException(CompletableFuture.java:323)
    at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:359)
    at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:364)
    at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:693)
    at java.base/java.util.concurrent.CompletableFuture$Completion.exec(CompletableFuture.java:527)
    at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:507)
    at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1458)
    at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:2034)
    at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:189)
Caused by: java.lang.NullPointerException: Cannot read field "owner" because "this.variableSymbol" is null
    at org.eclipse.jdt.internal.javac.dom.JavacVariableBinding.getKey(JavacVariableBinding.java:141)
    at org.eclipse.jdt.core.dom.JavacBindingResolver$Bindings.getVariableBinding(JavacBindingResolver.java:185)
    at org.eclipse.jdt.core.dom.JavacBindingResolver.resolveVariable(JavacBindingResolver.java:723)
    at org.eclipse.jdt.core.dom.VariableDeclaration.resolveBinding(VariableDeclaration.java:376)
    at org.eclipse.jdt.internal.corext.refactoring.rename.RenameAnalyzeUtil$ProblemNodeFinder.getProblemNodes(RenameAnalyzeUtil.java:88)
    at org.eclipse.jdt.internal.corext.refactoring.rename.RenameAnalyzeUtil.analyzeLocalRenames(RenameAnalyzeUtil.java:443)
    at org.eclipse.jdt.internal.corext.refactoring.rename.RenameAnalyzeUtil.analyzeLocalRenames(RenameAnalyzeUtil.java:402)
    at org.eclipse.jdt.internal.corext.refactoring.rename.RenameLocalVariableProcessor.doCheckFinalConditions(RenameLocalVariableProcessor.java:289)
    at org.eclipse.jdt.internal.corext.refactoring.rename.JavaRenameProcessor.checkFinalConditions(JavaRenameProcessor.java:51)
    at org.eclipse.ltk.core.refactoring.participants.ProcessorBasedRefactoring.checkFinalConditions(ProcessorBasedRefactoring.java:227)
    at org.eclipse.ltk.core.refactoring.Refactoring.checkAllConditions(Refactoring.java:163)
    at org.eclipse.ltk.core.refactoring.CheckConditionsOperation.run(CheckConditionsOperation.java:82)
    at org.eclipse.ltk.core.refactoring.CreateChangeOperation.run(CreateChangeOperation.java:116)
    at org.eclipse.jdt.ls.core.internal.handlers.RenameHandler.rename(RenameHandler.java:92)
    at org.eclipse.jdt.ls.core.internal.handlers.JDTLanguageServer.lambda$22(JDTLanguageServer.java:863)
    at org.eclipse.jdt.ls.core.internal.BaseJDTLanguageServer.lambda$0(BaseJDTLanguageServer.java:87)
    at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:690)
    ... 5 more

[gayanper]

@mickaelistria @datho7561 seems like in the parsing cycle of the code select before rename and parsing cycle before running the rename refactoring provides JC nodes with symbol null.

[gayanper]

Seems like the root cause is this which happens while resolving binding

java.lang.NullPointerException: Cannot invoke "javax.lang.model.element.Element.getKind()" because "elem" is null
java.lang.RuntimeException: java.lang.NullPointerException: Cannot invoke "javax.lang.model.element.Element.getKind()" because "elem" is null
    at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.invocationHelper(JavacTaskImpl.java:168)
    at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.analyze(JavacTaskImpl.java:379)
    at org.eclipse.jdt.core.dom.JavacBindingResolver.resolve(JavacBindingResolver.java:272)
    at org.eclipse.jdt.core.dom.JavacBindingResolver.resolvePackage(JavacBindingResolver.java:732)
    at org.eclipse.jdt.core.dom.PackageDeclaration.resolveBinding(PackageDeclaration.java:323)
    at org.eclipse.jdt.core.dom.JavacCompilationUnitResolver.resolveBindings(JavacCompilationUnitResolver.java:406)
    at org.eclipse.jdt.core.dom.JavacCompilationUnitResolver.resolveBindings(JavacCompilationUnitResolver.java:400)
    at org.eclipse.jdt.core.dom.JavacCompilationUnitResolver.toCompilationUnit(JavacCompilationUnitResolver.java:459)
    at org.eclipse.jdt.core.dom.ASTParser.internalCreateASTCached(ASTParser.java:1263)
    at org.eclipse.jdt.core.dom.ASTParser.lambda$0(ASTParser.java:1142)
    at org.eclipse.jdt.internal.core.JavaModelManager.cacheZipFiles(JavaModelManager.java:5762)
    at org.eclipse.jdt.core.dom.ASTParser.internalCreateAST(ASTParser.java:1142)
    at org.eclipse.jdt.core.dom.ASTParser.createAST(ASTParser.java:882)
    at org.eclipse.jdt.internal.corext.refactoring.util.RefactoringASTParser.parse(RefactoringASTParser.java:85)
    at org.eclipse.jdt.internal.corext.refactoring.rename.RenameAnalyzeUtil.analyzeLocalRenames(RenameAnalyzeUtil.java:419)
    at org.eclipse.jdt.internal.corext.refactoring.rename.RenameAnalyzeUtil.analyzeLocalRenames(RenameAnalyzeUtil.java:402)
    at org.eclipse.jdt.internal.corext.refactoring.rename.RenameLocalVariableProcessor.doCheckFinalConditions(RenameLocalVariableProcessor.java:289)
    at org.eclipse.jdt.internal.corext.refactoring.rename.JavaRenameProcessor.checkFinalConditions(JavaRenameProcessor.java:51)
    at org.eclipse.ltk.core.refactoring.participants.ProcessorBasedRefactoring.checkFinalConditions(ProcessorBasedRefactoring.java:227)
    at org.eclipse.ltk.core.refactoring.Refactoring.checkAllConditions(Refactoring.java:163)
    at org.eclipse.ltk.core.refactoring.CheckConditionsOperation.run(CheckConditionsOperation.java:82)
    at org.eclipse.ltk.core.refactoring.CreateChangeOperation.run(CreateChangeOperation.java:116)
    at org.eclipse.jdt.ls.core.internal.handlers.RenameHandler.rename(RenameHandler.java:92)
    at org.eclipse.jdt.ls.core.internal.handlers.JDTLanguageServer.lambda$22(JDTLanguageServer.java:863)
    at org.eclipse.jdt.ls.core.internal.BaseJDTLanguageServer.lambda$0(BaseJDTLanguageServer.java:87)
    at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:690)
    at java.base/java.util.concurrent.CompletableFuture$Completion.exec(CompletableFuture.java:527)
    at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:507)
    at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1458)
    at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:2034)
    at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:189)
Caused by: java.lang.NullPointerException: Cannot invoke "javax.lang.model.element.Element.getKind()" because "elem" is null
    at jdk.compiler/com.sun.tools.javac.model.JavacTypes.getOverriddenMethods(JavacTypes.java:337)
    at jdk.javadoc/jdk.javadoc.internal.doclint.Env.setCurrent(Env.java:192)
    at jdk.javadoc/jdk.javadoc.internal.doclint.Checker.scan(Checker.java:167)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$2.visitDecl(DocLint.java:297)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$DeclScanner.visitMethod(DocLint.java:448)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$DeclScanner.visitMethod(DocLint.java:425)
    at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:989)
    at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:92)
    at jdk.compiler/com.sun.source.util.TreeScanner.scan(TreeScanner.java:110)
    at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:118)
    at jdk.compiler/com.sun.source.util.TreeScanner.visitClass(TreeScanner.java:202)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$DeclScanner.visitClass(DocLint.java:443)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$DeclScanner.visitClass(DocLint.java:425)
    at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:896)
    at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:92)
    at jdk.compiler/com.sun.source.util.TreeScanner.scan(TreeScanner.java:110)
    at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:118)
    at jdk.compiler/com.sun.source.util.TreeScanner.visitCompilationUnit(TreeScanner.java:151)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$DeclScanner.visitCompilationUnit(DocLint.java:469)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$DeclScanner.visitCompilationUnit(DocLint.java:425)
    at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCCompilationUnit.accept(JCTree.java:625)
    at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:92)
    at jdk.javadoc/jdk.javadoc.internal.doclint.DocLint$3.started(DocLint.java:308)
    at jdk.compiler/com.sun.tools.javac.api.ClientCodeWrapper$WrappedTaskListener.started(ClientCodeWrapper.java:865)
    at jdk.compiler/com.sun.tools.javac.api.MultiTaskListener.started(MultiTaskListener.java:120)
    at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1347)
    at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1328)
    at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.analyze(JavacTaskImpl.java:404)
    at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.lambda$analyze$1(JavacTaskImpl.java:379)
    at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.invocationHelper(JavacTaskImpl.java:152)
    ... 30 more

[gayanper]

Seems like this a is JDK EA bug, any plans that we could make this incubator run both with last released JDK and next EA version at the same time ? IN other words could we make the EA builds only for testing purpose on CI and make last released version as the dependency to run the LS.

[gayanper]

I just removed the JDK-23 requirement from the vscode-java poc branch and point the ls.java-home to a JDK 22, this bug cannot be reproduced and LS runs perfectly fine. @fbricon Do you think we could remove the Java 23 requirement from the vscode-java-poc ?

[gayanper]

@mickaelistria I'm assuming we can close this issue since it is a JDK bug.

[mickaelistria]

@gayanper If you can reproduce this issue with plain Javac or with a simple demonstrator using only Javac APIs, please report it to https://bugs.java.com/

[gayanper]

@gayanper If you can reproduce this issue with plain Javac or with a simple demonstrator using only Javac APIs, please report it to https://bugs.java.com/

This happens randomly, i tried running with plain javac and also with maven multiple times. I think we can check again once we have more stable build available. I can check a more recent EA build as well.