[NETBEANS-4095] NPE saving Java file with type error in for-each

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 11.3
• Fix Version/s: 12.1
• Component/s: java - Source
• Labels: nbjavac

Environment

Java 14, NetBeans with nbjavac plugin installed

• Assignee: Arunava Sinha
• Reporter: Eirik Bakke
• Created: 01/Apr/20 03:43
• Updated: 05/Feb/21 21:33
• Resolved: 05/Aug/20 05:46

Description

If, during editing, a for-each loop appears with an incorrect pair of types, an error dialog shows up showing a NullPointerException every time the Java source file is saved, interrupting the user. A minimized example exhibiting this behavior is as follows:

public final class CausesVisitIterableForeachLoopNPE {
  public static final void main(String args[]) {
    final Map<String,Object> someMap = null;
    for (Object someVar : someMap) { }
  }
}

This example causes the IDE to throw the following exception:

java.lang.NullPointerException
	at com.sun.tools.javac.comp.Lower.visitIterableForeachLoop(Lower.java:3275)
	at com.sun.tools.javac.comp.Lower.visitForeachLoop(Lower.java:3162)
	at com.sun.tools.javac.tree.JCTree$JCEnhancedForLoop.accept(JCTree.java:1176)
	at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
	at com.sun.tools.javac.comp.Lower.translate(Lower.java:2080)
	at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:70)
	at com.sun.tools.javac.tree.TreeTranslator.visitBlock(TreeTranslator.java:167)
	at com.sun.tools.javac.comp.Lower.visitBlock(Lower.java:3347)
	at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:1036)
	at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
	at com.sun.tools.javac.comp.Lower.translate(Lower.java:2080)
	at com.sun.tools.javac.tree.TreeTranslator.visitMethodDef(TreeTranslator.java:150)
	at com.sun.tools.javac.comp.Lower.visitMethodDefInternal(Lower.java:2538)
	at com.sun.tools.javac.comp.Lower.visitMethodDef(Lower.java:2448)
	at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:882)
	at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
	at com.sun.tools.javac.comp.Lower.translate(Lower.java:2080)
	at com.sun.tools.javac.comp.Lower.visitClassDef(Lower.java:2219)
	at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:788)
	at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
	at com.sun.tools.javac.comp.Lower.translate(Lower.java:2080)
	at com.sun.tools.javac.comp.Lower.translate(Lower.java:2099)
	at com.sun.tools.javac.comp.Lower.translateTopLevelClass(Lower.java:3813)
	at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1691)
	at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1532)
	at com.sun.tools.javac.api.JavacTaskImpl$2.process(JavacTaskImpl.java:574)
	at com.sun.tools.javac.api.JavacTaskImpl$Filter.run(JavacTaskImpl.java:651)
	at com.sun.tools.javac.api.JavacTaskImpl.generate(JavacTaskImpl.java:577)
[catch] at org.netbeans.modules.java.source.nbjavac.indexing.MultiPassCompileWorker.compile(MultiPassCompileWorker.java:303)
	at org.netbeans.modules.java.source.indexing.JavaCustomIndexer.index(JavaCustomIndexer.java:361)
	at org.netbeans.modules.parsing.spi.indexing.Indexable$MyAccessor$2.run(Indexable.java:138)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater.runIndexer(RepositoryUpdater.java:275)
	at org.netbeans.modules.parsing.spi.indexing.Indexable$MyAccessor.index(Indexable.java:136)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work.doIndex(RepositoryUpdater.java:2750)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work.access$800(RepositoryUpdater.java:2154)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work$1.run(RepositoryUpdater.java:2636)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work$1.run(RepositoryUpdater.java:2634)
	at org.netbeans.modules.parsing.impl.indexing.errors.TaskCache.refreshTransaction(TaskCache.java:540)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work.index(RepositoryUpdater.java:2634)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work$3.call(RepositoryUpdater.java:3300)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work$3.call(RepositoryUpdater.java:3255)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$4.run(RepositoryUpdater.java:2127)
	at org.openide.util.lookup.Lookups.executeWith(Lookups.java:279)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater.runInContext(RepositoryUpdater.java:2123)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater.runInContext(RepositoryUpdater.java:2104)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater.access$1500(RepositoryUpdater.java:136)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work.scanFiles(RepositoryUpdater.java:3255)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$FileListWork.getDone(RepositoryUpdater.java:3785)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Work.doTheWork(RepositoryUpdater.java:3420)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Task._run(RepositoryUpdater.java:6183)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Task.access$4300(RepositoryUpdater.java:5834)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Task$2$1.run(RepositoryUpdater.java:6099)
	at org.openide.util.lookup.Lookups.executeWith(Lookups.java:279)
	at org.netbeans.modules.parsing.impl.RunWhenScanFinishedSupport.performScan(RunWhenScanFinishedSupport.java:83)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Task$2.call(RepositoryUpdater.java:6095)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Task$2.call(RepositoryUpdater.java:6091)
	at org.netbeans.modules.masterfs.filebasedfs.utils.FileChangedManager.priorityIO(FileChangedManager.java:153)
	at org.netbeans.modules.masterfs.providers.ProvidedExtensions.priorityIO(ProvidedExtensions.java:335)
	at org.netbeans.modules.parsing.nb.DataObjectEnvFactory.runPriorityIO(DataObjectEnvFactory.java:118)
	at org.netbeans.modules.parsing.impl.Utilities.runPriorityIO(Utilities.java:67)
	at org.netbeans.modules.parsing.impl.indexing.RepositoryUpdater$Task.run(RepositoryUpdater.java:6091)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1418)
	at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:45)
	at org.openide.util.lookup.Lookups.executeWith(Lookups.java:278)
	at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)

The problem occurs whether Compile-or-Save is enabled or not. Tested in a Maven Java project on Java 14.

Issue Links

• is related to: NETBEANS-4179 Assertion error in javac when saving file with missing comma in method parameter list