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Bug 528828

Summary:	NPE in CompletionEngine.findLocalMethods: method.returnType is null
Product:	[Eclipse Project] JDT	Reporter:	Friso Vrolijken <friso.vrolijken>
Component:	Core	Assignee:	Andreas Sewe <sewe>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	normal
Priority:	P3	CC:	sewe
Version:	4.7.1a
Target Milestone:	---
Hardware:	PC
OS:	Windows 10
Whiteboard:	stalebug

Description Friso Vrolijken

2017-12-15 06:26:54 EST

In my Error Log there are multiple messages like this. I don't know what caused them

-- Error Details --
Date: Fri Dec 15 11:27:04 CET 2017
Message: Exception during code completion
Severity: Error
Product: Eclipse 4.7.1.20171005-1200 (org.eclipse.epp.package.java.product)
Plugin: org.eclipse.recommenders.subwords.rcp
Exception Stack Trace:
java.lang.NullPointerException
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.findLocalMethods(CompletionEngine.java:9120)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.findMethods(CompletionEngine.java:10429)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.findVariablesAndMethods(CompletionEngine.java:12441)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.completionOnSingleNameReference(CompletionEngine.java:3670)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.complete(CompletionEngine.java:1920)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.complete(CompletionEngine.java:2233)
	at org.eclipse.jdt.internal.core.Openable.codeComplete(Openable.java:131)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:358)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:346)
	at org.eclipse.recommenders.internal.subwords.rcp.SubwordsSessionProcessor.computeProposals(SubwordsSessionProcessor.java:339)
	at org.eclipse.recommenders.internal.subwords.rcp.SubwordsSessionProcessor.getNewProposals(SubwordsSessionProcessor.java:228)
	at org.eclipse.recommenders.internal.subwords.rcp.SubwordsSessionProcessor.initializeContext(SubwordsSessionProcessor.java:168)
	at org.eclipse.recommenders.completion.rcp.processable.IntelligentCompletionProposalComputer.fireInitializeContext(IntelligentCompletionProposalComputer.java:293)
	at org.eclipse.recommenders.completion.rcp.processable.IntelligentCompletionProposalComputer.computeCompletionProposals(IntelligentCompletionProposalComputer.java:170)
	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:331)
	at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.computeCompletionProposals(ContentAssistProcessor.java:288)
	at org.eclipse.jface.text.contentassist.ContentAssistant$3.run(ContentAssistant.java:2007)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.jface.text.contentassist.ContentAssistant.computeCompletionProposals(ContentAssistant.java:2004)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.computeProposals(CompletionProposalPopup.java:560)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.access$7(CompletionProposalPopup.java:555)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup$2.run(CompletionProposalPopup.java:489)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.showProposals(CompletionProposalPopup.java:482)
	at org.eclipse.jface.text.contentassist.ContentAssistant.showPossibleCompletions(ContentAssistant.java:1823)
	at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitEditor$AdaptedSourceViewer.doOperation(CompilationUnitEditor.java:184)
	at org.eclipse.ui.texteditor.ContentAssistAction$1.run(ContentAssistAction.java:84)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
	at org.eclipse.ui.texteditor.ContentAssistAction.run(ContentAssistAction.java:81)
	at org.eclipse.jface.action.Action.runWithEvent(Action.java:473)
	at org.eclipse.jface.commands.ActionHandler.execute(ActionHandler.java:118)
	at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:92)
	at sun.reflect.GeneratedMethodAccessor145.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:55)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:305)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:239)
	at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:132)
	at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:152)
	at org.eclipse.core.commands.Command.executeWithChecks(Command.java:494)
	at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:487)
	at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:210)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.executeCommand(KeyBindingDispatcher.java:287)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.press(KeyBindingDispatcher.java:527)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.processKeyEvent(KeyBindingDispatcher.java:577)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.filterKeySequenceBindings(KeyBindingDispatcher.java:385)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.access$0(KeyBindingDispatcher.java:331)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher$KeyDownFilter.handleEvent(KeyBindingDispatcher.java:88)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:86)
	at org.eclipse.swt.widgets.Display.filterEvent(Display.java:1271)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1078)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1103)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1088)
	at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1130)
	at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1126)
	at org.eclipse.swt.widgets.Widget.wmChar(Widget.java:1547)
	at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:4962)
	at org.eclipse.swt.widgets.Canvas.WM_CHAR(Canvas.java:364)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:4843)
	at org.eclipse.swt.widgets.Canvas.windowProc(Canvas.java:359)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:5178)
	at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method)
	at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:2560)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3815)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1150)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1039)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:153)
	at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:680)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:594)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
	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:388)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:653)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:590)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1499)

Comment 1 Andreas Sewe

2017-12-18 04:42:22 EST

I(In reply to Friso Vrolijken from comment #0)
> In my Error Log there are multiple messages like this. I don't know what
> caused them

I'll investigate.

Comment 2 Andreas Sewe

2017-12-18 05:26:44 EST

Looking at the relevant code from JDT in Oxygen.1a (FWIW, hasn't change in Photon M4), it looks like method.returnType is null in the following fragment:
					proposal.setDeclarationPackageName(method.declaringClass.qualifiedPackageName());
					proposal.setDeclarationTypeName(method.declaringClass.qualifiedSourceName());
					proposal.setParameterPackageNames(parameterPackageNames);
					proposal.setParameterTypeNames(parameterTypeNames);
					proposal.setPackageName(method.returnType.qualifiedPackageName());
					proposal.setTypeName(method.returnType.qualifiedSourceName());
					proposal.setName(method.selector);

AFAIK, a non-null (compiler) MethodBinding with a null returnType TypeBinding shouldn't happen, but I may be mistaken.

Reassigning to JDT Core for comments.

Comment 3 Eclipse Genie

2020-02-09 20:16:20 EST

This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet. As such, we're closing this bug.

If you have further information on the current state of the bug, please add it and reopen this bug. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant.

--
The automated Eclipse Genie.