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The following incident was reported via the automated error reporting: code: 1 plugin: org.eclipse.recommenders.subwords.rcp_2.1.11.v20141027-2129 message: Exception during code completion fingerprint: bcb8920d exception class: java.lang.NullPointerException exception message: - number of children: 0 java.lang.NullPointerException: null at org.eclipse.jdt.ui.text.java.CompletionProposalCollector.<init>(CompletionProposalCollector.java:189) at org.eclipse.jdt.internal.ui.text.java.FillArgumentNamesCompletionProposalCollector.<init>(FillArgumentNamesCompletionProposalCollector.java:43) at org.eclipse.recommenders.completion.rcp.processable.ProposalCollectingCompletionRequestor.initalizeCollector(ProposalCollectingCompletionRequestor.java:56) at org.eclipse.recommenders.completion.rcp.processable.ProposalCollectingCompletionRequestor.<init>(ProposalCollectingCompletionRequestor.java:51) at org.eclipse.recommenders.internal.subwords.rcp.SubwordsSessionProcessor.computeProposals(SubwordsSessionProcessor.java:174) at org.eclipse.recommenders.internal.subwords.rcp.SubwordsSessionProcessor.getNewProposals(SubwordsSessionProcessor.java:148) at org.eclipse.recommenders.internal.subwords.rcp.SubwordsSessionProcessor.initializeContext(SubwordsSessionProcessor.java:105) at org.eclipse.recommenders.completion.rcp.processable.IntelligentCompletionProposalComputer.fireInitializeContext(IntelligentCompletionProposalComputer.java:218) at org.eclipse.recommenders.completion.rcp.processable.IntelligentCompletionProposalComputer.computeCompletionProposals(IntelligentCompletionProposalComputer.java:130) at org.eclipse.jdt.internal.ui.text.java.CompletionProposalComputerDescriptor.computeCompletionProposals(CompletionProposalComputerDescriptor.java:333) at org.eclipse.jdt.internal.ui.text.java.CompletionProposalCategory.computeCompletionProposals(CompletionProposalCategory.java:337) at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.collectProposals(ContentAssistProcessor.java:325) at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.computeCompletionProposals(ContentAssistProcessor.java:282) at org.eclipse.jface.text.contentassist.ContentAssistant.computeCompletionProposals(ContentAssistant.java:1861) at org.eclipse.jface.text.contentassist.CompletionProposalPopup.computeProposals(CompletionProposalPopup.java:573) at org.eclipse.jface.text.contentassist.CompletionProposalPopup.access$16(CompletionProposalPopup.java:570) at org.eclipse.jface.text.contentassist.CompletionProposalPopup$2.run(CompletionProposalPopup.java:505) at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70) at org.eclipse.jface.text.contentassist.CompletionProposalPopup.showProposals(CompletionProposalPopup.java:499) at org.eclipse.jface.text.contentassist.ContentAssistant.showPossibleCompletions(ContentAssistant.java:1687) at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitEditor$AdaptedSourceViewer.doOperation(CompilationUnitEditor.java:183) at org.eclipse.ui.texteditor.ContentAssistAction$1.run(ContentAssistAction.java:82) at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70) at org.eclipse.ui.texteditor.ContentAssistAction.run(ContentAssistAction.java:80) at org.eclipse.jface.action.Action.runWithEvent(Action.java:519) at org.eclipse.jface.commands.ActionHandler.execute(ActionHandler.java:122) at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:90) at sun.reflect.GeneratedMethodAccessor70.invoke(null:-1) at sun.reflect.DelegatingMethodAccessorImpl.invoke(null:-1) at java.lang.reflect.Method.invoke(null:-1) at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:55) at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:247) at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:229) at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:132) at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:149) at org.eclipse.core.commands.Command.executeWithChecks(Command.java:499) at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:508) at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:210) at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.executeCommand(KeyBindingDispatcher.java:286) at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.press(KeyBindingDispatcher.java:507) at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.processKeyEvent(KeyBindingDispatcher.java:558) at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.filterKeySequenceBindings(KeyBindingDispatcher.java:378) at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.access$0(KeyBindingDispatcher.java:324) at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher$KeyDownFilter.handleEvent(KeyBindingDispatcher.java:86) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84) at org.eclipse.swt.widgets.Display.filterEvent(Display.java:1262) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1060) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1085) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1070) at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1112) at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1108) at org.eclipse.swt.widgets.Widget.wmChar(Widget.java:1529) at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:4722) at org.eclipse.swt.widgets.Canvas.WM_CHAR(Canvas.java:343) at org.eclipse.swt.widgets.Control.windowProc(Control.java:4610) at org.eclipse.swt.widgets.Canvas.windowProc(Canvas.java:339) at org.eclipse.swt.widgets.Display.windowProc(Display.java:5023) at org.eclipse.swt.internal.win32.OS.DispatchMessageW(OS.java:-2) at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:2549) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3759) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1151) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1032) at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:148) at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:636) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:579) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150) at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:135) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:382) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:236) at sun.reflect.NativeMethodAccessorImpl.invoke0(null:-2) at sun.reflect.NativeMethodAccessorImpl.invoke(null:-1) at sun.reflect.DelegatingMethodAccessorImpl.invoke(null:-1) at java.lang.reflect.Method.invoke(null:-1) at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:648) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:603) at org.eclipse.equinox.launcher.Main.run(Main.java:1465) General Information: reported-by: Nikolay Metchev anonymous-id: 7e94eadc-9077-32e2-8a41-c3f5581e059d eclipse-build-id: 4.4.0.I20140606-1215 eclipse-product: org.eclipse.epp.package.jee.product operating system: Windows8 6.2.0 (x86_64) - win32 jre-version: 1.8.0_25-b18 The following plug-ins were present on the execution stack (*): 1. org.eclipse.core.commands_3.6.100.v20140528-1422 2. org.eclipse.core.databinding.observable_1.4.1.v20140210-1835 3. org.eclipse.core.databinding_1.4.1.v20140214-0004 4. org.eclipse.core.runtime_3.10.0.v20140318-2214 5. org.eclipse.e4.core.commands_0.10.2.v20140424-2344 6. org.eclipse.e4.core.contexts_1.3.100.v20140407-1019 7. org.eclipse.e4.core.di_1.4.0.v20140414-1837 8. org.eclipse.e4.ui.bindings_0.10.200.v20140424-2042 9. org.eclipse.e4.ui.workbench_1.1.0.v20140528-1949 10. org.eclipse.e4.ui.workbench.swt_0.12.100.v20140530-1436 11. org.eclipse.equinox.app_1.3.200.v20130910-1609 12. org.eclipse.equinox.launcher_1.3.0.v20140415-2008 13. org.eclipse.jdt.ui_3.10.1.v20140817-1500 14. org.eclipse.jdt_3.10.0.v20140925-0400 15. org.eclipse.jface_3.10.0.v20140604-0740 16. org.eclipse.jface.text_3.9.0.v20140521-1657 17. org.eclipse.recommenders.completion.rcp_2.1.11.v20141027-2129 18. org.eclipse.recommenders.subwords.rcp_2.1.11.v20141027-2129 19. org.eclipse.swt_3.103.0.v20140605-2008 20. org.eclipse.ui_3.106.0.v20140519-0906 21. org.eclipse.ui.ide.application_1.0.500.v20140514-2033 22. org.eclipse.ui.ide_3.10.0.v20140521-1937 Please note that: * Messages, stacktraces, and nested status objects may be shortened. * Bug fields like status, resolution, and whiteboard are sent back to reporters. * The list of present bundles and their respective versions was calculated by package naming heuristics. This may or may not reflect reality. Other Resources: * Report: https://dev.eclipse.org/recommenders/committers/confess/#/problems/54c4f314bee810030da0a9b9 * Manual: https://dev.eclipse.org/recommenders/community/confess/#/guide Thank you for your assistance. Your friendly error-reports-inbox.
Johannes, can you investigate?
Did some analysis. The problematic lines seem to be JavaContentAssistInvocationContext newjdtContext = new JavaContentAssistInvocationContext(viewer, triggerOffset, editor); ICompilationUnit cu = newjdtContext.getCompilationUnit(); Here, according to the JavaDoc, cu can be null, which causes the NPE further down the line. (FWIW, JDT guards itself, against null ICompilationUnits in JavaCompletionProposalComputer.internalComputeCompletionProposals.) I think the relevant change is f057e2b [1], which changed where the CU is taken from. Previously, it was ICompilationUnit cu = crContext.getCompilationUnit(); now it uses the newly created newJdtContext to get the CU from. Interestingly, we can be sure to have a CU available (otherwise SubwordsSessionProcessor.initializeContext would fail), so I wonder why [1] uses the JavaContentAssistInvocationContext(viewer, triggerOffset, editor) constructor rather than JavaContentAssistInvocationContext(cu) with the CU off which we know that it is non-null? Marcel, as you wrote the code in [1] initially, can you shed some light onto this? [1] <https://git.eclipse.org/c/recommenders/org.eclipse.recommenders.git/commit/?id=f057e2b86f49d7cdfaab733f28e186313d346d8f>
(In reply to Andreas Sewe from comment #2) > Marcel, as you wrote the code in [1] initially, can you shed some light onto > this? > > [1] > <https://git.eclipse.org/c/recommenders/org.eclipse.recommenders.git/commit/ > ?id=f057e2b86f49d7cdfaab733f28e186313d346d8f> We need to set the invocation location. That's why I created a new context. I don't understand why there is an NPE b/c public ICompilationUnit getCompilationUnit() { if (!fCUComputed) { ... IJavaElement je= EditorUtility.getEditorInputJavaElement(fEditor, false); if (je instanceof ICompilationUnit) fCU= (ICompilationUnit)je; } ... 'should' work. While I can think of a workaround, I'd like to further investigate and understand the situation where this happens. Maybe any of the reporters can provide an example. Will contact them.
*** This bug has been marked as a duplicate of bug 463860 ***
