Comment 1 Marcel Bruch 2012-05-19 07:15:10 EDT

Another stacktrace with other locations but same problem:

java.lang.IllegalArgumentException
	at org.eclipse.jdt.core.Signature.appendTypeArgumentSignatures(Signature.java:825)
	at org.eclipse.jdt.core.Signature.appendClassTypeSignature(Signature.java:615)
	at org.eclipse.jdt.core.Signature.appendTypeSignature(Signature.java:911)
	at org.eclipse.jdt.core.Signature.appendTypeSignature(Signature.java:855)
	at org.eclipse.jdt.core.Signature.toCharArray(Signature.java:2637)
	at org.eclipse.jdt.core.Signature.getSignatureSimpleName(Signature.java:1870)
	at org.eclipse.jdt.core.Signature.getSignatureSimpleName(Signature.java:1914)
	at org.eclipse.jdt.internal.core.SourceMapper$LocalVariableElementKey.<init>(SourceMapper.java:96)
	at org.eclipse.jdt.internal.core.SourceMapper.enterAbstractMethod(SourceMapper.java:836)
	at org.eclipse.jdt.internal.core.SourceMapper.enterMethod(SourceMapper.java:774)
	at org.eclipse.jdt.internal.compiler.SourceElementNotifier.notifySourceElementRequestor(SourceElementNotifier.java:368)
	at org.eclipse.jdt.internal.compiler.SourceElementNotifier.notifySourceElementRequestor(SourceElementNotifier.java:693)
	at org.eclipse.jdt.internal.compiler.SourceElementNotifier.notifySourceElementRequestor(SourceElementNotifier.java:455)
	at org.eclipse.jdt.internal.compiler.SourceElementParser.parseCompilationUnit(SourceElementParser.java:934)
	at org.eclipse.jdt.internal.core.SourceMapper.mapSource(SourceMapper.java:1404)
	at org.eclipse.jdt.internal.core.SourceMapper.mapSource(SourceMapper.java:1339)
	at org.eclipse.jdt.internal.core.ClassFile.mapSource(ClassFile.java:659)
	at org.eclipse.jdt.internal.core.ClassFile.openBuffer(ClassFile.java:635)
	at org.eclipse.jdt.internal.core.Openable.getBuffer(Openable.java:288)
	at org.eclipse.jdt.internal.core.ClassFile.getBuffer(ClassFile.java:359)
	at org.eclipse.jdt.internal.core.BinaryMember.getCategories(BinaryMember.java:98)
	at org.eclipse.jdt.internal.ui.viewsupport.JavaElementLabelComposer.appendCategoryLabel(JavaElementLabelComposer.java:630)
	at org.eclipse.jdt.internal.ui.viewsupport.JavaElementLabelComposer.appendTypeLabel(JavaElementLabelComposer.java:1025)
	at org.eclipse.jdt.internal.ui.viewsupport.JavaElementLabelComposer.appendElementLabel(JavaElementLabelComposer.java:285)
	at org.eclipse.jdt.ui.JavaElementLabels.getElementLabel(JavaElementLabels.java:531)
	at org.eclipse.jdt.ui.JavaElementLabels.getStyledElementLabel(JavaElementLabels.java:506)
	at org.eclipse.jdt.ui.JavaElementLabels.getStyledTextLabel(JavaElementLabels.java:434)
	at org.eclipse.jdt.internal.ui.viewsupport.JavaUILabelProvider.getStyledText(JavaUILabelProvider.java:178)
	at org.eclipse.jface.viewers.DelegatingStyledCellLabelProvider.getStyledText(DelegatingStyledCellLabelProvider.java:195)
	at org.eclipse.jface.viewers.DecoratingStyledCellLabelProvider.getStyledText(DecoratingStyledCellLabelProvider.java:192)
	at org.eclipse.jface.viewers.DelegatingStyledCellLabelProvider.update(DelegatingStyledCellLabelProvider.java:103)
	at org.eclipse.jface.viewers.DecoratingStyledCellLabelProvider.update(DecoratingStyledCellLabelProvider.java:134)
	at org.eclipse.jface.viewers.ViewerColumn.refresh(ViewerColumn.java:152)
	at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:953)
	at org.eclipse.jface.viewers.AbstractTreeViewer$UpdateItemSafeRunnable.run(AbstractTreeViewer.java:113)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
	at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
	at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:1033)
	at org.eclipse.jface.viewers.StructuredViewer$UpdateItemSafeRunnable.run(StructuredViewer.java:485)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
	at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
	at org.eclipse.jface.viewers.StructuredViewer.updateItem(StructuredViewer.java:2167)
	at org.eclipse.jface.viewers.StructuredViewer.internalUpdate(StructuredViewer.java:2150)
	at org.eclipse.jface.viewers.StructuredViewer.update(StructuredViewer.java:2089)
	at org.eclipse.jface.viewers.ColumnViewer.update(ColumnViewer.java:554)
	at org.eclipse.jface.viewers.StructuredViewer.update(StructuredViewer.java:2033)
	at org.eclipse.jface.viewers.StructuredViewer.handleLabelProviderChanged(StructuredViewer.java:1191)
	at org.eclipse.jdt.internal.ui.javaeditor.JavaOutlinePage$JavaOutlineViewer.handleLabelProviderChanged(JavaOutlinePage.java:454)
	at org.eclipse.jface.viewers.ContentViewer$1.labelProviderChanged(ContentViewer.java:97)
	at org.eclipse.jface.viewers.BaseLabelProvider$1.run(BaseLabelProvider.java:74)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
	at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
	at org.eclipse.jface.viewers.BaseLabelProvider.fireLabelProviderChanged(BaseLabelProvider.java:72)
	at org.eclipse.jface.viewers.DecoratingStyledCellLabelProvider$1.labelProviderChanged(DecoratingStyledCellLabelProvider.java:77)
	at org.eclipse.ui.internal.decorators.DecoratorManager$1.run(DecoratorManager.java:430)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.ui.internal.decorators.DecoratorManager.fireListener(DecoratorManager.java:428)
	at org.eclipse.ui.internal.decorators.DecorationScheduler$3.runInUIThread(DecorationScheduler.java:530)
	at org.eclipse.ui.progress.UIJob$1.run(UIJob.java:95)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:135)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3940)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3617)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1021)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:915)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:86)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:585)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:540)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:124)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1438)

Comment 2 Deepak Azad 2012-05-19 07:31:28 EDT

(In reply to comment #0)
> I'm yet not able to identify the cause but when navigating to other source
> files I get an error popup. the stacktrace below is what gets logged. All open
> files do not contain compile errors.

Stacktrace indicates that you did a Ctrl+Click. Can you also include the source  file and the location where you did that?

Comment 3 Marcel Bruch 2012-05-19 07:44:41 EDT

It seems that whatever method of KMeansCluster I *select*, e.g. in outline view, it raises this exception.

e.g. org.apache.mahout.clustering.kmeans.KMeansClusterer.clusterPoints(Iterable<Vector>, List<Cluster>, DistanceMeasure, int, double))


The class is contained in a binary plug-in project. Should I attach this project?

Comment 4 Deepak Azad 2012-05-19 08:00:41 EDT

(In reply to comment #3)
> The class is contained in a binary plug-in project. Should I attach this
> project?
That should also be good enough.

Comment 5 Marcel Bruch 2012-05-19 08:13:47 EDT

The mahout project is a bit large (33mb). I made the project temporarily available here: https://www.dropbox.com/s/o1sdvatzz5y3w5n/org.apache.mahout.zip

Comment 6 Stephan Herrmann 2012-05-19 10:04:48 EDT

Thanks for the example, Marcel.

I can reproduce.

I see it fail even when just opening class KMeansCluster in an editor.
In my case it falls over a scrambled type signature of method
  public void emitPointToNearestCluster(org.apache.mahout.math.Vector point, Iterable clusters, org.apache.hadoop.mapreduce.Mapper$Context context)

The third parameter has this type signature:
  Lorg/apache/hadoop/mapreduce/Mapper<**Lorg/apache/hadoop/io/Text;Lorg/apache/mahout/clustering/ClusterObservations;>.Context;

but the BinaryMethod ends up with this type signature:
  QMapper<**QText;QContext;
i.e., we are missing this section:
  Lorg/apache/mahout/clustering/ClusterObservations;>.

Upon failing to find the terminating '>' we read over the end of the singature.

I'm investigating what makes us drop the mentioned section.

It seems to be related to the '.', like we would interpret this
  Lorg/apache/mahout/clustering/ClusterObservations;>.Context;
as a qualified name whose last segment in "Context", without noticing
the intermediate '>'!

Comment 7 Ayushman Jain 2012-05-19 10:50:31 EDT

This happens inside org.eclipse.jdt.internal.core.SourceMapper.convertTypeNamesToSigs(char[][]) , which converts 
Mapper<?,?,Text,ClusterObservations>.Context
to an invalid signature:
QMapper<**QText;QContext;

This is because convertTypeNamesToSigs creates unqualified signatures, converting, eofr example, QX<QMap.Entry> to QX<QEntry> by recording the position of the last 'Q' and the next obtained dot. However, in the given scenario, the last recorded Q belongs to ClusterObservations but the '.' belongs to Mapper => The bug is that '>' is not handled at all.

This, however is an old standing bug.

Comment 8 Ayushman Jain 2012-05-19 10:51:00 EDT

(In reply to comment #6)
> Thanks for the example, Marcel.
> 
> I can reproduce.
Oops, mid-air collision! :)

Comment 9 Ayushman Jain 2012-05-19 10:52:07 EDT

Created attachment 215901 [details]
patch under test

Comment 10 Stephan Herrmann 2012-05-19 11:05:56 EDT

(In reply to comment #8)
> (In reply to comment #6)
> > Thanks for the example, Marcel.
> > 
> > I can reproduce.
> Oops, mid-air collision! :)

Now I had the collision, while writing pretty much the same analysis.
You beat me to it :)
So we seem to agree.

Comment 11 Sebastian Zarnekow 2012-05-19 11:14:37 EDT

I'm not too much into the code in SourceMapper but the suggested patch seems to fail for nested qualified inner types, e.g.

Mapper<?,?,Text,Mapper<?,?,Text,ClusterObservations>.Context>.Context

produces

QMapper<**QText;QContextQContext;

whereas I'd expect

QContext;

Comment 12 Sebastian Zarnekow 2012-05-19 11:18:11 EDT

Iterable<Mapper<?,?,Text,ClusterObservations>.Context>

will yield 

QIterable<QContextQContext;>;

which does not look right either.

Comment 13 Stephan Herrmann 2012-05-19 11:19:25 EDT

(In reply to comment #11)
> I'm not too much into the code in SourceMapper but the suggested patch seems to
> fail for nested qualified inner types, e.g.

exactly, we need to somehow count nesting levels

Comment 14 Ayushman Jain 2012-05-19 12:23:01 EDT

(In reply to comment #12)
> Iterable<Mapper<?,?,Text,ClusterObservations>.Context>
> 
> will yield 
> 
> QIterable<QContextQContext;>;
> 
> which does not look right either.
Yeah, mine was a "weekend patch" :)

Anyway, I dont think this will make it to Juno. Srikanth, I'll target this for 4.3 , unless you think otherwise.

Comment 15 Stephan Herrmann 2012-05-19 19:26:52 EDT

Created attachment 215908 [details]
alternative patch

Here's a somewhat more refined solution (incl. a little main for easy
testing / playing).

For some more or less random examples here's what it does:

java.lang.String
->	QString;
apache.Mapper<?,?,ap.Text,ap.ClusterObservations>.Context
->	QContext;
apache.Mapper<?,?,ap.Text,ap.ClusterObservations>.Context<java.lang.String>
->	QContext<QString;>;
app.Mapper<?,?,ap.Text,ap2.ClusterObservations>
->	QMapper<**QText;QClusterObservations;>;
Context<String>
->	QContext<QString;>;
Mapper<?,?,Text,ClusterObservations>.Context<String>
->	QContext<QString;>;
Iterable<Mapper<?,?,Text,ClusterObservations>.Context>
->	QIterable<QContext;>;
java.util.Iterable<Mapper<?,?,Text,ClusterObservations>.Context>
->	QIterable<QContext;>;
Mapper<?,?,Text,Mapper<?,?,Text,ClusterObservations>.Context>.Context
->	QContext;


While this bug doesn't seem to be a regression it has bad consequences
for someone trying to work with specific (legal!) class files.

The patch uses a small lookahead function to find the matching '>'
for a given '<'. I noticed that methods in SourceMapper and Signature
tend to process strings in a single loop. I tried another solution first,
which indeed avoids the lookahead, but that solution is significantly
more involved.

My patch passes all of JDT/Core's tests. 
New unit tests still need to be written.

Comment 16 Ayushman Jain 2012-05-21 03:03:27 EDT

Stephan, thanks for the patch. Assigning it to you so that you can release it in 3.9 / 4.3 M1

Comment 17 Stephan Herrmann 2012-08-28 10:52:12 EDT

Released for 4.3 M2 via http://git.eclipse.org/c/jdt/eclipse.jdt.core.git/commit/?id=7df383b00e8453025afa0d0c65533607ef343fe1

White box tests have been added to class SignatureTests (I needed to make one internal method public for access by unit tests, but I think this is OK since the class itself is internal too, shouldn't be accessed by clients anyway).

Comment 18 Srikanth Sankaran 2012-09-18 04:57:04 EDT

Verified for 4.3 M2 via code inspection

Comment 19 Stephan Herrmann 2012-10-04 12:47:38 EDT

*** Bug 391030 has been marked as a duplicate of this bug. ***