[GROOVY-2262] groovy.lang.MetaClassRegistry$MetaClassCreationHandle.create() causing java.lang.StackOverflowError

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 1.1-rc-1
• Fix Version/s: 1.1-rc-3
• Component/s: groovy-jdk
• Environment: Windows XP; Eclipse Europa 3.3 & command line groovy; ; D:\Profiles\Adam\Desktop\Delegate Test>groovy -v; Groovy Version: 1.1-rc-1 JVM: 1.6.0_03-b05
• Assignee: Unassigned
• Reporter: Adam Rinehart
• Created: 03/Nov/07 11:32
• Updated: 22/Dec/07 07:10
• Resolved: 13/Nov/07 01:42

Description

I was attempting to create a custom delegate class for a third party library. Researching this, I found the following page:
http://docs.codehaus.org/display/GROOVY/Using+the+Delegating+Meta+Class

When I tried to follow the "Package Name Convention Solution", by creating a FuzzyVariableMetaClass file in groovy.runtime.metaclass.ncr.fuzzyj.FuzzyVariableMetaClass, I got a java.lang.StackOverflowError. This was with no inherited methods. I only created the shell of the class and constructor.

As a test, I followed the instructions on the page, creating a StringMetaClass as documented on the page. This also gave me the java.lang.StackOverflowError. When I ran this in the Eclipse debugger, the problem appears to occur during the groovy.lang.MetaClassRegistry$MetaClassCreationHandle.create(Class theClass, MetaClassRegistry registry) call.

Specifically, this method does the following
--------------------
final Class customMetaClass = Class.forName("groovy.runtime.metaclass." + theClass.getName() + "MetaClass");
final Constructor customMetaClassConstructor = customMetaClass.getConstructor(new Class[]

{MetaClassRegistry.class, Class.class}

);
return (MetaClass)customMetaClassConstructor.newInstance(new Object[]

{registry, theClass}

);
---------------------
This calls the constructor on the new MetaClass we are creating, which calls DelegateMetaClass's constructor, which calls GroovySystem.getMetaClassRegistry().getMetaClass(...), which calls getMetaClassFor(theClass), which calls metaClassCreationHandle.create(theClass, this), completing the infinite loop.

I have NOT tested this under Groovy 1.0. But I imagine it worked then since the webpage has not been updated since Jan 28, 2007.

------------------------
I also ran into issues when I tried the "InvokeHelper Solution " on the same page. Those errors were different and will be entered as a separate bug.