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Bug 334498

Summary:

[DI] ContextInjectionFactory.make on nested class within @PostConstruct method of outer class leads to endless recursion

Product:

[Eclipse Project] Platform

Reporter:

Paul Reuter <preuter>

Component:

Runtime

Assignee:

Oleg Besedin <ob1.eclipse>

Status:

RESOLVED FIXED

QA Contact:

Severity:

normal

Priority:

CC:

ob1.eclipse, remy.suen

Version:

4.1

Target Milestone:

4.2 M1

Hardware:

OS:

Mac OS X - Carbon (unsup.)

Whiteboard:

Attachments:

Description	Flags
Is this the problem?	none
Trying to duplicate	none
Patch	none

Description Paul Reuter

2011-01-17 04:28:35 EST

Build Identifier: I20101216-1305

This seems to be related to a JDK bug in Constructor.getGenericParameterTypes:

http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5087240

Is there a possible workaround?

Reproducible: Always

Steps to Reproduce:
1. Create nested class with @Inject annotated constructor
2. Within outer class in @PostConstruct annotated method, call ContextInjectionFactory.make(NestedClass.class, context)

Comment 1 Oleg Besedin

2011-01-17 11:37:12 EST

Created attachment 186923 [details]
Is this the problem?

Can you attach sample code that causes endless recursion? I tried to follow your description but what I am getting is an InjectionException which is more-or-less what is expected, see the attached code.

Comment 2 Paul Reuter

2011-01-18 01:29:54 EST

Ah, I found the reason your test case does not reproduce the bug:

in org.eclipse.e4.core.internal.di.InjectorImpl.internalMake:298
// unless this is the default constructor, it has to be tagged
if (!constructor.isAnnotationPresent(Inject.class) && constructor.getParameterTypes().length != 0)
	continue;


Adding @Inject to the constructor of the nested class does the trick for me.

The reason for the endless recursion is the following:

In org.eclipse.e4.core.internal.di.InjectorImpl.resolveArgs:391,

the argument descriptors returned by 

org.eclipse.e4.core.internal.di.ConstructorRequestor.getDependentObjects()

include the outer class as first argument, which is then later created, thereby triggering the @PostConstruct and subsequent endless recursion.

Comment 3 Paul Reuter

2011-01-18 04:41:08 EST

On a related note, the necessity of the @Inject annotation on the default constructor is also a bug, I think. 

Since the default constructor of a nested class has the outer class as first parameter, it is not recognized as default constructor by the code-snippet above.

Comment 4 Oleg Besedin

2011-01-18 10:08:00 EST

Created attachment 187005 [details]
Trying to duplicate

Hmm... I've added @Inject to constructor and still getting an injection exception, not an endless loop.

Comment 5 Paul Reuter

2011-01-24 11:05:49 EST

Oh my, found some egg on my face. I never actually ran this bug in "Run" mode, which pops up an InjectionException after a few seconds (still outrageous for something so simple). 

In debug mode, this takes long enough that I never actually waited it out, so I did not realize the unspectacular ending.

Could you place a breakpoint in the @PostConstruct method and observe if you hit it more than the one time that is expected?

Comment 6 Oleg Besedin

2011-06-20 11:56:58 EDT

Created attachment 198265 [details]
Patch

Comment 7 Oleg Besedin

2011-06-24 09:39:52 EDT

Patch applied to CVS Head.

Comment 8 Oleg Besedin

2011-06-24 09:40:23 EDT

Thanks Paul for taking time to figure this out!